Appendix E — SUSTAINABLE PRACTICES

(Matrix Adoption Tables are non-regulatory, intended only as an aid to the code user. See Chapter 1 for state agency authority and building applications.)

This state agency does not adopt sections identified with the following symbol: † The Office of the State Fire Marshal’s adoption of this chapter or individual sections is applicable to structures regulated by other state agencies pursuant to Section 1.11.0.

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APPENDIX E

SUSTAINABLE PRACTICES

The provisions contained in this appendix are not mandatory unless specifically adopted by a state agency, or referenced in the adopting ordinance.

E 101.0 General.

E 101.1 Applicability. The purpose of this appendix is to provide a comprehensive set of technically sound provisions that encourage sustainable practices and works towards enhancing the design and construction of mechanical systems that result in a positive long-term environmental impact. This appendix is not intended to circumvent the health, safety, and general welfare requirements of this code.

E 201.0 Definitions.

E 201.1 General. For the purpose of this appendix, the following definitions shall apply: Cycles of Concentration for Cooling Towers. Cycles of concentration equals the specific conductance of the water in the cooling tower basin divided by the combined flowweighted average specific conductance of the makeup water(s) to the cooling tower.

Duct Wall Penetrations. Includes pipe, tubing, rods, and wire. Screws and other fasteners are not considered to be ductwork penetrations.

Energy Star. A joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy. Energy Star is a voluntary program designed to identify and promote energy-efficient products and practices.

Fan Array. Multiple fans in parallel between two plenum sections in an air distribution system. [ASHRAE 90.1:3.2]

Fan, Embedded. A fan that is part of a manufactured assembly where the assembly includes functions other than air movement. [ASHRAE 90.1:3.2]

Fan Energy Index (FEI). The ratio of the electric input power of a reference fan to the electric input power of the actual fan as calculated per AMCA 208. [ASHRAE 90.1:3.2]

Fan Nameplate Electrical Input Power. The nominal electrical input power rating stamped on a fan assembly nameplate. [ASHRAE 90.1:3.2]

Fan System Electrical Power. The sum of the fan electrical power of all fans that are required to operate at fan system design conditions to supply air from the heating or cooling source to the conditioned spaces and/or return it to the source or exhaust it to the outdoors. [ASHRAE 90.1:3.2]

Heating Seasonal Performance Factor (HSPF). The total heating output of a heat pump during its normal annual usage period for heating in British thermal units (Btu) (kW•h) divided by the total electric energy input during the same period. [ASHRAE 90.1:3.2]

Humidistatic Controls. Automatic controls used to maintain humidity at a fixed or adjustable set point. [ASHRAE 90.1:3.2]

Integrated Energy Efficiency Ratio (IEER). A singlenumber figure of merit expressing cooling part-load EER efficiency for commercial unitary air-conditioning and heat pump equipment on the basis of weighted operation at various load capacities for the equipment. [ASHRAE 90.1:3.2] Integrated Part-Load Value (IPLV.I-P). A single-number figure of merit based on part-load EER, COP C, or kW/kW expressing part-load efficiency for air-conditioning and heat pump equipment on the basis of weighted operation at various load capacities for the equipment. [ASHRAE 90.1:3.2]

Joint, Transverse . Connections of two duct sections oriented perpendicular to airflow. Maintenance. The upkeep of property or equipment by the owner of the property in accordance with the requirements of this appendix. Minimum Efficiency Reporting Value (MERV). Filter minimum efficiency reporting value, in accordance with ASHRAE 52.2.

Multi-Occupant Spaces. Indoor spaces used for presentations and training, including classrooms and conference

rooms.

On-Site Renewable Energy. Energy generated from renewable sources produced at the building site. [ASHRAE 90.1:3.2] Packaged Terminal Air Conditioner (PTAC). A wall sleeve and a separate unencased combination of heating and cooling assemblies specified by the manufacturer and intended for mounting through the wall. It includes refrigeration components, separable outdoor louvres, forced ventilation, and heating availability by purchaser’s choice of hot water, steam, or electrical resistance heat.

Packaged Terminal Heat Pump (PTHP). A separate unencased refrigeration system installed in a cabinet having a function and configuration similar to that of a packaged terminal air-conditioner. It uses reverse cycle refrigeration as its prime heat source and should have other supplementary heat source(s) available to purchasers with the choice of hot water, steam, or electric resistance heat.

Parking Garage Section. A part of a parking garage where airflow is restricted from other parts of the garage by solid walls. [ASHRAE 90.1:3.2]

Process Application. A manufacturing, industrial, or commercial procedure or activity where the primary purpose is other than conditioning spaces and maintaining comfort and amenities for the occupants of a building. [ASHRAE 90.1:3.2] Recirculation System. A system of hot water supply and return piping with shutoff valves, balancing valves, circulating pumps, and a method of controlling the circulating system.

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APPENDIX E

Renewable Energy Resources. Energy from solar, wind, biomass or hydro, or extracted from hot fluid or steam heated within the earth. [ASHRAE 90.1:3.2] Seam, Longitudinal . Joints oriented in the direction of airflow.

Seasonal Energy Efficiency Ratio (SEER). The total cooling output of an air conditioner during its normal annual usage period for cooling in Btu (kW•h) divided by the total electric energy input during the same period in Btu (kW•h).

[ASHRAE 90.1:3.2] Site-Recovered Energy. Waste energy recovered at the building site that is used to offset consumption of purchased fuel or electrical energy supplies. [ASHRAE 90.1:3.2] Stormwater. Natural precipitation that has contacted a surface at grade or below grade and has not been put to beneficial use.

Thermal Energy. The amount of sensible heat energy stored within a material or fluid. The product of the mass, specific thermal capacity and temperature increase/decrease of the material or fluid. Also known as sensible heat energy. Thermal Storage. A tank or vessel used in a solar thermal, hydronic, or geothermal system, in which thermal energy is stored.

Total Dissolved Solids (TDS). A measure (by electrical conductivity) of the amount of soluble matter that is present in the water.

Whole House Fan. A fan used for ventilating a building or space primarily to exhaust air from the conditioned space typically through an attic.

E 301.0 General Regulations. E 301.1 Installation. Mechanical systems covered by this appendix shall be installed in accordance with this code, other applicable codes, and the manufacturer’s installation and operating instructions. E 301.2 Qualifications. Where permits are required, the Authority Having Jurisdiction shall have the authority to require contractors, installers, or service technicians to demonstrate competency. Where determined by the Authority Having Jurisdiction, the contractor, installer or service technician shall be licensed to perform such work.

E 302.0 Disposal of Liquid Waste. E 302.1 Disposal. It shall be unlawful for a person to cause, suffer, or permit the disposal of liquid wastes, in a place or manner, except through and by means of an approved drainage system, installed and maintained in accordance with the provisions of the plumbing code. E 302.2 Connections to Plumbing System Required. Equipment and appliances, used to receive or discharge liquid wastes or sewage, shall be connected to the drainage system of the building or premises in accordance with the requirements of the plumbing code and this appendix.

by means of an approved drainage system, installed and maintained in accordance with the provisions of the plumbing code. E 302.2 Connections to Plumbing System Required. Equipment and appliances, used to receive or discharge liquid wastes or sewage, shall be connected to the drainage system of the building or premises in accordance with the requirements of the plumbing code and this appendix.

E 303.0 Abandonment.

E 303.1 General. An abandoned system or part thereof covered under the scope of this appendix shall be disconnected

from remaining systems, drained, plugged, and capped in an approved manner.

E 401.0 Water Conservation and Efficiency. E 401.1 General. The provisions of this section establish the means of conserving potable and nonpotable water used in and around a building.

E 402.0 Meters.

E 402.1 Required. A water meter shall be required for buildings connected to a public water system, including municipally supplied reclaimed (recycled) water. In other than single-family houses, multi-family structures not exceeding three stories above grade, and modular houses, a separate meter or submeter shall be installed in the following locations:

(1) The makeup water supply to cooling towers, evaporative condensers, and fluid coolers. (2) The makeup water supply to one or more boilers collectively exceeding 1 000 000 British thermal units per hour (Btu/h) (293 kW). (3) The water supply to a water-using process where the consumption exceeds 1000 gallons per day (gal/d) (0.0438 L/s), except for manufacturing processes. (4) The makeup water supply to an evaporative cooler having an air flow exceeding 30 000 cubic feet per minute (ft [3] /min) (14.1584 m [3] /s). E 402.2 Consumption Data. A means of communicating water consumption data from submeters to the water consumer shall be provided. E 402.3 Access. Meters and submeters shall be accessible.

E 403.0 HVAC Water Use.

E 403.1 Once-Through Cooling. Once-through cooling using potable water is prohibited. E 403.2 Cooling Towers and Evaporative Coolers. Cooling towers and evaporative coolers shall be equipped with makeup water and blow down meters, conductivity controllers, and overflow alarms. Cooling towers shall be equipped with efficiency drift eliminators that achieve drift reduction to 0.002 percent of the circulated water volume for counterflow towers and 0.005 percent for cross-flow towers. E 403.3 Cooling Tower Makeup Water. Not less than 5 cycles of concentration is required for air-conditioning cooling tower makeup water having a total hardness of less than 11 grains per gallon (gr/gal) (188 mg/L) expressed as calcium carbonate. Not less than 3.5 cycles of concentration is required for air-conditioning cooling tower makeup water having a total hardness equal to or exceeding 11 gr/gal (188 mg/L) expressed as calcium carbonate. Exception: Air-conditioning cooling tower makeup water having discharge conductivity range not less than 7 gr/gal (120 mg/L) to 9 gr/gal (154 mg/L) of silica measured as silicon dioxide.

rbonate. Not less than 3.5 cycles of concentration is required for air-conditioning cooling tower makeup water having a total hardness equal to or exceeding 11 gr/gal (188 mg/L) expressed as calcium carbonate. Exception: Air-conditioning cooling tower makeup water having discharge conductivity range not less than 7 gr/gal (120 mg/L) to 9 gr/gal (154 mg/L) of silica measured as silicon dioxide.

E 403.4 Evaporative Cooler Water Use. Evaporative cooling systems shall use 3.5 gallons (13.2 L) or less of water per ton-hour (kW•h) of cooling where system controls are set to maximum water use. Water use expressed in maximum

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APPENDIX E

water use per ton-hour (kW•h) of cooling, shall be marked on the device and included in the product user manual, product information literature, and manufacturer’s installation instructions. Water use information shall be readily available at the time of code compliance inspection.

E 403.4.1 Overflow Alarm. Cooling systems shall be equipped with an overflow alarm to alert building owners, tenants, or maintenance personnel where the water refill valve continues to allow water to flow into the

reservoir where the reservoir is full. The alarm shall have a sound pressure level rating of not less than 85 dBa measured at a distance of 10 feet (3048 mm).

E 403.4.2 Automatic Pump Shutoff. Cooling systems shall automatically cease pumping water to the evaporation pads where airflow across evaporation pads

ceases.

E 403.4.3 Cooler Reservoir Discharge. A water quality management system (either timer or water quality sensor) shall be provided. Where timers are used, the time interval between discharge of reservoir water shall be set to 6 or more hours of cooler operation. Where water quality sensors are used, the discharge of reservoir water shall be set for 800 ppm or more of total dissolved solids (TDS). Continuous discharge or continuous bleed systems shall not be installed.

E 403.4.4 Discharge Water Reuse. Discharge water shall be reused where applications exist on site. Where a nonpotable water source system exists on site, evaporative cooler discharge water shall be collected and discharged to the collection system.

Exception: Where the reservoir water affects the quality of the nonpotable water supply making the nonpotable water unusable for its intended purposes.

E 403.4.5 Discharge Water to Drain. Where discharge water is not recovered for reuse, the sump overflow line shall not be directly connected to a drain. Where the discharge water is discharged into a sanitary drain, an air gap of not less than 6 inches (152 mm) shall be provided between the termination of the discharge line and the drain opening. The discharge line shall terminate in a location that is visible to the building owner, tenants, or maintenance personnel.

red for reuse, the sump overflow line shall not be directly connected to a drain. Where the discharge water is discharged into a sanitary drain, an air gap of not less than 6 inches (152 mm) shall be provided between the termination of the discharge line and the drain opening. The discharge line shall terminate in a location that is visible to the building owner, tenants, or maintenance personnel.

E 403.5 Use of Reclaimed (Recycled) and Onsite Treated Nonpotable Water for Cooling. Where approved for use by the water or wastewater utility and the Authority Having Jurisdiction, reclaimed (recycled), or onsite treated nonpotable water shall be permitted to be used for industrial and commercial cooling or air-conditioning.

E 403.5.1 Drift Eliminator. A drift eliminator shall be utilized in a cooling system, utilizing alternate sources of water, where the aerosolized water is capable of coming in contact with employees or members of the public.

E 403.5.2 Disinfection. A biocide shall be used to treat the cooling system recirculation water where the recycled water is capable of coming in contact with employees or members of the public.

E 501.0 Heating, Ventilation, and Air-Conditioning Systems and Equipment – Energy Efficiency. E 501.1 Scope. The provisions of this section shall establish the means of enhancing energy efficiency associated with mechanical systems in a building.

E 502.0 Heating, Ventilation, and Air-Conditioning Low-Rise Residential Buildings. E 502.1 General. The heating, ventilating, air-conditioning, for single-family houses, multi-family structures not exceeding three stories above grade, and modular houses shall be in accordance with Section E 502.2 through Section E 502.12. The heating, ventilation, and air-conditioning system of other buildings shall be in accordance with Section E 503.0. E 502.2 Heating, Ventilating, and Air-Conditioning Systems and Equipment. This section shall regulate only equipment using single-phase electric power, air conditioners, and heat pumps with rated cooling capacities less than 65 000 British thermal units per hour (Btu/h) (19 kW), warm air furnaces with rated heating capacities less than 225 000 Btu/h (66 kW), boilers less than 300 000 Btu/h (88 kW) input, and heating-only heat pumps with rated heating capacities less than 65 000 Btu/h (19 kW). [ASHRAE 90.2:6.2] E 502.2.1 Nonresidential Type Systems and Equipment. Heating, ventilating, and air-conditioning systems and equipment that do not fall under the requirements of Section E 502.0 shall be in accordance with the applicable requirements of Section E 503.0. E 502.3 Balancing. The air distribution system design, including outlet grilles, shall provide a means for balancing the air distribution system unless the design procedure provides a system intended to operate within plus or minus 10 percent of design air quantities. [ASHRAE 90.2:6.3] E 502.3.1 Balancing Dampers. Balancing dampers shall be installed in branch ducts, and the axis of the damper shall be installed parallel to the direction of airflow in the main duct.

illes, shall provide a means for balancing the air distribution system unless the design procedure provides a system intended to operate within plus or minus 10 percent of design air quantities. [ASHRAE 90.2:6.3] E 502.3.1 Balancing Dampers. Balancing dampers shall be installed in branch ducts, and the axis of the damper shall be installed parallel to the direction of airflow in the main duct.

E 502.4 Ducts. Ducts shall be sized, installed, and tested in accordance with Section E 502.4.1 through Section E 502.4.4.

E 502.4.1 Insulation for Ducts. Portions of the air distribution system installed in or on buildings for heating and cooling shall be R-8. Where the mean outdoor dewpoint temperature in a month exceeds 60°F (16°C), vapor retarders shall be installed on conditioned-air supply ducts. Vapor retarders shall have a water vapor permeance not exceeding 0.5 perm [2.87 E-11 kg/(Pa•s•m [2] )] where tested in accordance with Procedure A in ASTM E96.

Insulation shall not be required where the ducts are within the conditioned space. [ASHRAE 90.2:6.4] E 502.4.2 Ducts and Register Penetrations. Joints, seams, and penetrations of duct systems shall be made airtight by means of mastics, gasketing, or other means in accordance with this code. Register penetrations shall be sealed to the wall or floor assemblies. Where HVAC duct penetrates a conditioned space, the duct penetration shall be sealed to the wall or floor assembly to prevent leakage into an unconditioned space.

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APPENDIX E

E 502.4.3 Duct Leakage Test. For systems with a duct or air handler outside of the conditioned space, a duct leakage test shall be performed in accordance with Section E 502.4.3.1.

E 502.4.3.1 Duct Leakage Verification Test. Ductwork shall be tested to the maximum permitted leakage in 1 cubic foot per minute (ft [3] /min) per 100 square feet [0.0001 (m [3] /s)/m [2] ] of duct surface area in accordance with SMACNA HVAC Air Duct Leakage Test Manual. Register penetrations shall be sealed during the test. The test shall be conducted with a pressure differential of 0.1 inch water gauge (0.02 kPa) across the tested system.

E 502.4.4 Duct Sizing. Duct systems shall be sized in accordance with ACCA Manual D or other methods approved by the Authority Having Jurisdiction with the velocity in the main duct not to exceed 1000 feet per minute (ft/min) (5.08 m/s) and the velocity in the secondary branch duct not to exceed 600 ft/min (3.048 m/s). E 502.5 Insulation for Piping. HVAC system piping installed to serve buildings and within buildings shall be thermally insulated in accordance with Table E 502.5. [ASHRAE 90.2-2007:6.5] E 502.6 Ventilation and Combustion Air. The building shall be designed to have the capability to provide the venti

TABLE E 502.5 MINIMUM PIPE INSULATION THICKNESS [1, 5 ]

[ASHRAE 90.2-2007: TABLE 6.5]

For SI Units: °C= (°F-32)/1.8, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/(m•K)], 1 inch = 25 mm

Notes: 1 For insulation outside the stated conductivity range, the minimum thickness ( T ) shall be determined as follows: T = r {(1 + t/r) [K/k ] – 1}

Where:

T = minimum insulation thickness (inches). r = actual outside radius of pipe (inches) (mm). t = insulation thickness listed in this table for applicable fluid temperature and pipe size. K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu•in/(h•ft [2] - °F)] [W/(m•K)]. k = the upper value of the conductivity range listed in this table for the applicable fluid temperature. 2 These thicknesses are based on energy efficiency considerations only. Additional insulation is sometimes required relative to safety issues/surface temperature. 3 Piping insulation is not required between the control valve and coil on run-outs where the control valve is located within 4 feet (1219 mm) of the coil and the pipe size is 1 inch (25 mm) or less. 4 These thicknesses are based on energy efficiency considerations only. Issues such as water vapor permeability or surface condensation sometimes require vapor retarders, additional insulation or both. 5 For piping exposed to outdoor air, increase insulation thickness by 1 ⁄ 2 of an inch (12.7 mm). The outdoor air is defined as any portion of insulation that is exposed to outdoor air. For example, attic spaces and crawl spaces are considered exposed to outdoor air.

TABLE E 502.6

VENTILATION AIR

[ASHRAE 90.2-2007: TABLE 6.6.1]

For SI units: 1 cubic foot per minute = 0.0283 m [3] /min, 1 cubic foot per minute = 0.4719 L/s

Notes: 1 Calculate in accordance with Equation E 502.6. 2 Reference standards:

(a) ACCA Manual J (b) ASHRAE GRP-158

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APPENDIX E

lation air specified in Table E 502.6. Mechanical ventilation shall be calculated in accordance with Equation E 502.6.

(Equation E 502.6)

Mechanical Ventilation = [(0.35 – Summer ) × Volume ] / 60

Where:

Mechanical Ventilation = required mechanical ventilation rate to supplement summer infiltration, CFM

Summer = summer design infiltration rate, ACH Volume = volume of conditioned space, ft [3 ] (m [3] )

For SI units: 1 cubic foot = 0.0283 m [3], 1 cubic foot per minute = 0.00047 m [3] /s, 1 cubic foot per minute = 0.4719 L/s

[ASHRAE 90.2-2007:6.6.1]

E 502.6.1 Combustion Air. Combustion air for fossil fuel heating equipment shall comply with this code or with one of the following:

(1) Natural gas and propane heating equipment, NFPA 54

(2) Oil heating equipment, NFPA 31

(3) Solid fuel burning equipment, NFPA 211

[ASHRAE 90.2-2007:6.6.2] E 502.7 Electric Heating Systems. Electric heating systems shall be installed in accordance with the following requirements. [ASHRAE 90.2-2007:6.7] E 502.7.1 Wall, Floor, or Ceiling Electric-Resis- tance Heating. Where wall, floor, or ceiling electricresistance heating units are used, the structure shall be zoned and heaters installed in each zone in accordance with the heat loss of that zone. Where living and sleeping zones are separate, the number of zones shall be not less than two. Where two or more heaters are installed in one room, they shall be controlled by one thermostat.

[ASHRAE 90.2-2007:6.7.1]

E 502.7.2 Electric Central Warm Air Heating. Where electric central warm air heating is to be installed, an electric heat pump or an off-peak electric heating system with thermal storage shall be used.

Exceptions:

(1) Electric resistance furnaces where the ducts are located inside the conditioned space, and not less than two zones are provided where the living and sleeping zones are separate.

(2) Packaged air-conditioning units with supplemental electric heat. [ASHRAE 90.2-2007:6.7.2] E 502.8 Bath Ceiling Units. Bath ceiling units providing a combination of heat, light, or ventilation shall be provided with controls permitting separate operation of the heating function. [ASHRAE 90.2-2007:6.8] E 502.9 HVAC Equipment, Rated Combinations. HVAC system equipment and system components shall be furnished with the input(s), the output(s), and the value of the appropriate performance descriptor of HVAC products in accordance with federal law or in accordance with Table E 502.9, as applicable. These shall be based on newly produced equipment or components. Manufacturer’s instructions shall be furnished with and attached to the equipment. The manufacturer of electric-resistance heating equipment shall furnish full-load energy input over the range of voltages at which the equipment is intended to operate. [ASHRAE 90.2-2007:6.9] E 502.10 Controls. Each system or each zone within a system shall be provided with not less than one thermostat capable of being set from 55°F (13°C) to 85°F (29°C) and capable of operating the system’s heating and cooling. The thermostat or control system, or both, shall have an adjustable deadband, the range of which includes a setting of 10°F (6°C) between heating and cooling where automatic changeover is provided. Wall-mounted temperature controls shall be mounted on an inside wall. [ASHRAE 90.2-2007:6.10.1] E 502.10.1 Initial Control Setting. The control shall initially be set for a maximum heating temperature of 70°F (21°C) and a cooling temperature of not less than 78°F (26°C).

E 502.10.2 Ventilation Control. Each mechanical ventilation system (supply, exhaust, or both) shall be equipped with a readily accessible switch or other means for shutoff. Manual or automatic dampers installed for the purpose of isolating outside air intakes and exhausts from the air distribution system shall be designed for tight shutoff.

[ASHRAE 90.2-2007:6.10.2]

TABLE E 502.9

MINIMUM REQUIREMENTS FOR NON-FEDERALLY COVERED HVAC EQUIPMENT

[ASHRAE 90.2-2007: TABLE 6.9]

For SI units: °C = (°F-32)/1.8

• Performance for electrically powered equipment with capacity less than 65 000 Btu/h (19 kW) where rated in accordance with ARI 325.

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APPENDIX E

E 502.10.3 Humidity Control. Where additional energy-consuming equipment is provided for adding moisture to maintain specific selected relative humidities in spaces or zones, a humidistat shall be provided. This device shall be capable of being set to prevent energy from being used to produce relative humidity within the space above 30 percent. [ASHRAE 90.2-2007:6.10.3.1] E 502.10.3.1 Cooling. Where additional energyconsuming equipment is provided for reducing humidity, it shall be equipped with controls capable of being set to prevent energy from being used to produce a relative humidity within the space below 50 percent during periods of human occupancy and below 60 percent during unoccupied periods.

[ASHRAE 90.2-2007:6.10.3.2] E 502.10.4 Freeze Protection Systems and Snow/Ice Melting. Freeze protection systems, such as heat tracing of outdoor piping and heat exchangers, including self-regulating heat tracing, shall include automatic controls capable of and configured to shut off the systems where outdoor air temperatures are above 40°F (4°C) or where the conditions of the protected fluid will prevent freezing. Snow- and ice-melting systems shall include automatic controls capable of and configured to shut off the systems where the pavement temperature is above 50°F (10°C) and no precipitation is falling and an automatic or manual control that will allow shutoff where the outdoor temperature is above 40°F (4°C) so that the potential for snow or ice accumulation is negligible.

[ASHRAE 90.1:6.4.3.7] E 502.10.5 Other Controls. Where setback, zoned, humidity and cooling controls and equipment are provided, they shall be designed and installed in accordance with Section E 502.10 through Section E 502.10.3.1.

[ASHRAE 90.2-2007:6.10.3.3]

E 502.11 Whole House Fans. Whole house exhaust fans

shall have insulated louvers or covers which close where the

fan is off. Covers or louvers shall have an insulation value of not less than R-4.2, and shall be installed in accordance with the manufacturer’s installation instructions. The attic openings shall be sufficient to accommodate the ventilation capacity of the whole house fan. The operation of the whole house fan shall be considered in determining the adequacy of providing combustion air in accordance with this code. E 502.12 Dampers. Dampers shall be installed to close off outdoor air inlets and exhaust outlets where the ventilation system is not operating.

E 503.0 Heating, Ventilation, and Air-Conditioning – Other than Low-Rise Residential Buildings. E 503.1 General. The heating, ventilation, and air-conditioning in buildings, other than single-family houses, multi-family structures of not more than three stories above grade, and modular houses, shall be in accordance with Section E 503.0.

E 503.1.1 New Buildings. Mechanical equipment and systems serving the heating, cooling, ventilating, or refrigeration needs of new buildings shall comply with the requirements of this section as described in Section E 503.2. [ASHRAE 90.1:6.1.1.1]

E 503.1.2 Additions to Existing Buildings. Mechanical equipment and systems serving the heating, cooling, ventilating, or refrigeration needs of additions to existing buildings shall be in accordance with the requirements of this section as described in Section E 503.2.

Exception: Where HVACR to an addition is provided by existing HVACR systems and equipment, such existing systems and equipment shall not be required to be in accordance with this appendix. A new system or equipment installed shall be in accordance with specific requirements applicable to those systems and equipment.

[ASHRAE 90.1:6.1.1.2]

E 503.1.3 Alterations to Heating, Ventilating, Air- Conditioning, and Refrigeration in Existing Buildings. New HVACR equipment as a direct replacement of existing HVACR equipment shall comply with the following sections as applicable for the equipment being replaced:

(1) Section E 503.3 “Simplified Approach Option for HVAC Systems”

(2) Section E 503.4 “Equipment Efficiencies, Verification, and Labeling Requirements”

(3) Section E 503.4.6 “Zone Thermostatic Controls”

(4) Section E 503.4.6.2 “Set-point Overlap Restrictions”

(5) Section E 503.4.6.3 “Off-Hour Controls” except for Section E 503.4.6.3.4, “Zone Isolation”

(6) Section E 503.4.6.4 “Ventilation System Controls”

(7) Section E 503.4.6.8 “Freeze Protection and Snow/Ice Melting Systems”

(8) Section E 503.4.6.9 “Ventilation Controls for HighOccupancy Areas” only for single-zone equipment

(9) Section E 503.4.6.11 “Heated or Cooled Vestibules”

(10)Section E 503.4.8 “Walk-In Coolers and Walk-In Freezers”

(11)Section E 503.5.1 “Air Economizers” for units located outdoors

(12)Section E 503.5.3 “Integrated Economizer Control”

(13)Section E 503.5.4 “Economizer Heating System Impact”

(14)Section E 503.5.6.1.2 “Fan Efficiency”

(15)Section E 503.5.6.2 “Supply Fan Airflow Control”

(16)Section E 503.5.6.5 “Fractional Horsepower (Kilowatt) Fan Motors”

(17)Section E 503.5.7 “Boiler Turndown”

(18)Section E 503.5.7.3 “Chiller and Boiler Isolation”

(19)Section E 503.5.8.1 “Fan Speed Control.” [ASHRAE 90.1:6.1.1.3.1]

E 503.1.3.1 New Cooling Systems. New cooling systems installed to serve previously uncooled spaces shall be in accordance with this section as described in Section E 503.2. [ASHRAE 90.1:6.1.1.3.2]

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APPENDIX E

E 503.1.3.2 Existing Cooling Systems. Alterations to existing cooling systems shall not decrease economizer capability unless the system is in accordance with Section E 503.5 through Section E 503.5.4.1. [ASHRAE 90.1:6.1.1.3.3]

E 503.1.3.3 Ductwork. New and replacement ductwork shall comply with Section E 503.4.7.1 through Section E 503.4.7.2.1. [ASHRAE 90.1:6.1.1.3.4]

E 503.1.3.4 Piping. New and replacement piping shall comply with Section E 503.4.7.1.

Exceptions:

(1) For equipment that is being modified or repaired but not replaced, provided that such modifications or repairs will not result in an increase in the annual energy consumption of the equipment using the same energy type.

(2) Where a replacement or alteration of equipment requires extensive revisions to other systems, equipment, or elements of a building, and such replaced or altered equipment is a like-for-like replacement.

(3) For a refrigerant change of existing equipment.

(4) For the relocation of existing equipment.

(5) For ducts and piping where there is insufficient space or access to comply with these requirements. [ASHRAE 90.1:6.1.1.3.5] E 503.2 Compliance Paths. Mechanical equipment and systems providing heating, cooling, ventilating, or refrigeration shall comply with Section E 503.2.1 and Section E 503.2.2. [ASHRAE 90.1:6.2]

E 503.2.1 Requirements for All Compliance Paths. Mechanical equipment and systems shall comply with the following:

(1) Section E 503.0, “General”

(2) Section E 503.4, “Equipment Efficiencies, Verification, and Labeling Requirements”

(3) Section E 503.6, “Submittals”

(4) Section E 503.7, “Minimum Equipment Efficiency Tables.” [ASHRAE 90.1:6.2.1]

E 503.2.2 Additional Requirements. Mechanical equipment and systems shall comply with one of the following:

(1) Section E 503.3, “Simplified Approach Building Compliance Path for HVAC Systems”

Exception: When compliance is shown using Section E 503.2.2(1), compliance with Section E 503.4 is not required.

(2) Section E 503.5, “Prescriptive Compliance Path”

Exception: HVAC systems only serving the heating, cooling, or ventilating needs of a computer room with IT equipment load greater than 10 kW (34 000 Btu/h) shall be permitted to comply with Section E 503.4, “Equipment Efficiencies, Verification, and Labeling Requirements” and Section E

503.8, “Alternative Compliance Path, Computer Room Systems.” [ASHRAE 90.1:6.2.2] E 503.3 Simplified Approach Building Compliance Path for HVAC Systems. The simplified approach shall be an optional path for compliance where the following conditions are met:

(1) The building is not more than two stories in height. (2) Gross floor area is less than 25 000 square feet (2322.6 m [2] ).

(3) The HVAC system in the building is in accordance with the requirements listed in Section E 503.3.1. [ASHRAE 90.1:6.3.1] E 503.3.1 Criteria. The HVAC system shall comply with all of the following criteria:

(1) The system serves a single HVAC zone.

(2) The equipment shall comply with the variable flow requirements of Section E 503.5.6.2.

(3) Cooling (where any) shall be provided by a unitary packaged or split-system air conditioner that is either air-cooled or evaporatively cooled, with efficiency that is in accordance with the requirements shown in Table E 503.7.1(1) for air conditioners, Table E 503.7.1(2) for heat pumps, or Table E 503.7.1(4) for packaged terminal and room air conditioners and heat pumps for the applicable equipment category.

ere any) shall be provided by a unitary packaged or split-system air conditioner that is either air-cooled or evaporatively cooled, with efficiency that is in accordance with the requirements shown in Table E 503.7.1(1) for air conditioners, Table E 503.7.1(2) for heat pumps, or Table E 503.7.1(4) for packaged terminal and room air conditioners and heat pumps for the applicable equipment category.

(4) The system shall have an air economizer in accordance with Section E 503.5 and Section E 503.4.6.13.

(5) Heating (where any) shall be provided by a unitary packaged or split-system heat pump that is in accordance with the applicable efficiency requirements shown in Table E 503.7.1(2) for heat pumps or Table E 503.7.1(4) for packaged terminal and room air conditioners and heat pumps, a fuel-fired furnace that is in accordance with the applicable efficiency requirements shown in Table E 503.7.1(5) for furnaces, duct furnaces, and unit heaters, an electric resistance heater, or a baseboard system connected to a boiler that is in accordance with the applicable efficiency requirements shown in Table E 503.7.1(6) for boilers.

(6) The system shall comply with the exhaust air energy recovery requirements in accordance with Section E 503.5.10.1.2.

(7) The system shall be controlled by a manual changeover or dual setpoint thermostat.

(8) Where a heat pump equipped with auxiliary internal electric resistance heaters is installed, controls shall be provided that prevent supplemental heater operation where the heating load is capable of being met by the heat pump alone during both steady-state operation and setback recovery. Supplemental heater operation shall be permitted during outdoor coil defrost cycles. The heat pump shall be controlled in accordance with one of the following:

(a) A digital or electronic thermostat designed for heat pump use that energizes auxiliary heat where the heat pump has insufficient capacity

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

to maintain setpoint or to warm up the space at a sufficient rate.

(b) A multistage space thermostat and an outdoor air thermostat wired to energize auxiliary heat on the last stage of the space thermostat and where outdoor air temperature is less than 40°F (4°C).

Exceptions: Heat pumps that comply with the following:

(1) Have a minimum efficiency regulated by NAECA.

(2) In accordance with the requirements shown in Table E 503.7.1(2).

(3) Include all usage of internal electric resistance heating.

(9) The system controls shall not permit reheat or other form of simultaneous heating and cooling for humidity control.

(10)Systems serving spaces other than residential spaces, that do not require continuous operation with a cooling or heating capacity more than 7000 Btu/h (2.1 kW) shall comply with Section E 503.4.6.3.1 and Section E 503.4.6.3.2.

(11) Systems serving residential spaces other than hotel/motel guest rooms shall comply with Section E 503.4.6.3.1 and Section E 503.4.6.3.2 except for electric resistance heaters rated at 5000 Btu/h (1.5 kW) or less with a readily accessible manual control that lowers the set point or turns the unit off.

(12) Systems serving hotel/motel guest rooms shall comply with Section E 503.4.6.3.5.

(13) Except for piping within manufacturer’s units, HVAC piping shall be insulated in accordance with Table E 503.7.3(1) and Table E 503.7.3(2). Insulation exposed to weather shall be suitable for outdoor service, e.g., protected by aluminum, sheet metal, painted canvas, or plastic cover. Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation.

(14) Ductwork and plenums shall be insulated in accordance with Table E 503.7.2 and shall be sealed in

accordance with Section E 503.4.7.2.

(15) Construction documents shall require a ducted system to be air balanced in accordance with industryaccepted procedures.

(16) Outdoor air intake and exhaust systems shall comply with Section E 503.4.6.4 through Section E 503.4.6.5.

(17) Where separate heating and cooling equipment serves the same temperature zone, thermostats shall be interlocked to prevent simultaneous heating and cooling.

(18) Systems with a design supply air capacity more than 10 000 ft [3] /min (4.7195 m [3] /s) shall have optimum start controls.

(19) The system shall comply with the demand control ventilation requirements of Section E 503.4.6.9, occupied-standby controls in Section E 503.5.6.8, and the ventilation design requirements of Section E 503.5.6.7.

(20) The system shall comply with the door switch requirements of Section E 503.5.14. [ASHRAE 90.1:6.3.2]

E 503.3.2 Climate Zone Determination. Climate zones identified in this appendix shall be determined in accordance with ASHRAE 90.1. For locations in the United States and its territories, the assigned climate zone and, where required, the assigned climate zone letter shall be in accordance with ASHRAE 169.

Exception: Where recorded historical climatic data are available for a construction site, it is permitted to be used to determine compliance where approved by the Authority Having Jurisdiction. [ASHRAE 90.1:5.1.4.1]

E 503.4 Equipment Efficiencies, Verification, and Labeling Requirements. Equipment shown in Table E 503.7.1(1) through Table E 503.7.1(20) shall have a minimum performance at the specified rating conditions when tested in accordance with the specified test procedure. Where multiple rating conditions or performance requirements are provided, the equipment shall satisfy all stated requirements unless otherwise exempted by footnotes in the table. Equipment covered under the Federal Energy Policy Act of 1992 (EPACT) shall have no minimum efficiency requirements for operation at minimum capacity or other than standard rating conditions. Equipment used to provide service water-heating functions as part of a combination system shall satisfy all stated requirements for the appropriate space heating or cooling category.

y footnotes in the table. Equipment covered under the Federal Energy Policy Act of 1992 (EPACT) shall have no minimum efficiency requirements for operation at minimum capacity or other than standard rating conditions. Equipment used to provide service water-heating functions as part of a combination system shall satisfy all stated requirements for the appropriate space heating or cooling category.

Tables are as follows:

(1) Table E 503.7.1(1), “Electrically Operated Unitary Air Conditioners and Condensing Units—Minimum Efficiency Requirements” (2) Table E 503.7.1(2), “Electrically Operated Air-Cooled Unitary Heat Pumps—Minimum Efficiency Requirements”

(3) Table E 503.7.1(3), “Water-Chilling Packages—Minimum Efficiency Requirements” (See Section E 503.4.1 for water-cooled centrifugal water-chilling packages that are designed to operate at nonstandard conditions.) (4) Table E 503.7.1(4), “Electrically Operated Packaged Terminal Air Conditioners, Packaged Terminal Heat Pumps, Single-Package Vertical Air Conditioners, Single-Package Vertical Heat Pumps, Room Air Conditioners, and Room Air Conditioner Heat Pumps—Minimum Efficiency Requirements” (5) Table E 503.7.1(5), “Warm-Air Furnaces and Combination Warm-Air Furnaces/Air-Conditioning Units, WarmAir Duct Furnaces, and Unit Heaters—Minimum Efficiency Requirements”

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APPENDIX E

(6) Table E 503.7.1(6), “Gas- and Oil-Fired Boilers—Minimum Efficiency Requirements” (7) Table E 503.7.1(7), “Performance Requirements for Heat-Rejection Equipment—Minimum Efficiency Requirements” (8) Table E 503.7.1(8), “Electrically Operated VariableRefrigerant-Flow Air Conditioners—Minimum Efficiency Requirements”

(9) Table E 503.7.1(9), “Electrically Operated VariableRefrigerant-Flow and Applied Heat Pumps—Minimum Efficiency Requirements”

(10)Table E 503.7.1(10), “Floor-Mounted Air Conditioners and Condensing Units Serving Computer Rooms”

(11)Table E 503.7.1(11), “Commercial Refrigerators, Commercial Freezers, Freezers, and Refrigeration—Minimum Efficiency Requirements”

(12)Table E 503.7.1(12), “Vapor-Compression-Based Indoor Pool Dehumidifiers—Minimum Efficiency Requirements”

(13) Table E 503.7.1(13), “Electrically Operated DX-DOAS Units, Single-Package and Remote Condenser, without Energy Recovery—Minimum Efficiency Requirements”

(14)Table E 503.7.1(14), “Electrically Operated DX-DOAS Units, Single-Package and Remote Condenser, with Energy Recovery—Minimum Efficiency Requirements”

(15)Table E 503.7.1(15), “Electrically Operated WaterSource Heat Pumps—Minimum Efficiency Requirements”

(16)Table E 503.7.1(16), “Heat Pump and Heat Recovery Chiller Packages—Minimum Efficiency Requirement”

(17)Table E 503.7.1(17), “Ceiling-Mounted Computer-Room Air Conditioners—Minimum Efficiency Requirements”

(18)Table E 503.7.1(18), “Walk-In Cooler and Freezer Display Door Efficiency Requirements”

(19)Table E 503.7.1(19), “Walk-In Cooler and Freezer Nondisplay Door Efficiency Requirements” (20)Table E 503.7.1(20), “Walk-In Cooler and Freezer Refrigeration System Efficiency Requirements”

[ASHRAE 90.1:6.4.1.1] E 503.4.1 Water-Cooled Centrifugal Chilling Packages. Equipment not designed for operation in accordance with AHRI 550/590 test conditions of

44.00°F (6.67°C) leaving and 54.00°F (12.22°C) entering chilled-fluid temperatures, and with 85.00°F (29.44°C) entering and 94.30°F (34.61°C) leaving condenser-fluid temperatures, shall have maximum full-load kW/ton ( FL ) and part-load rating requirements adjusted in accordance with Equation E 503.4.1(1) through Equation E 503.4.1(3):

FLadj = FL / Kadj [Equation E 503.4.1(1)] PLVadj = IPLV.IP / Kadj [Equation E 503.4.1(2)] Kadj = A x B [Equation E 503.4.1(3)]

Where:

FL = full-load kW/ton value from Table E

503.7.1(3) FLadj = maximum full-load kW/ton rating, adjusted for nonstandard conditions

IPLV.IP = IPLV.IP value from Table E 503.7.1(3) PLVadj = maximum NPLV rating, adjusted for nonstandard conditions

A = 0.00000014592 x (LIFT ) [4] - 0.0000346496 x ( LIFT ) [3] + 0.00314196 x ( LIFT ) [2] 0.147199 x ( LIFT ) + 3.93073

B = 0.0015 x LvgEvap + 0.934

LIFT = LvgCond - LvgEvap

LvgCond = Full-load condenser leaving fluid temperature (°F)

LvgEvap = Full-load evaporator leaving temperature (°F)

The FLadj and PLVadj values shall only be applicable for centrifugal chillers meeting all of the following full-load design ranges:

(1) 36.00°F (2.22°C) ≤ LvgEvap ≤ 60.00°F (15.56°C)

(2) LvgCond ≤ 115.00°F (46.11°C)

(3) 20.00°F (-6.67°C) ≤ LIFT ≤ 80.00°F (26.67°C) Manufacturers shall calculate the FLadj and PLVadj before determining whether to label the chiller in accordance with Section E 503.4.3. Chillers that are in accor dance with ASHRAE 90.1 shall be labeled on chillers in

accordance with the scope of ASHRAE 90.1.

Centrifugal chillers designed to operate outside of these ranges shall not be covered under this appendix.

Example: Path A, 600 ton (600 000 kg) centrifugal chiller Table E 503.7.1(3) efficiencies.

FL = 0.5600 kW/ton

IPLV.IP = 0.5000 kW/ton

LvgCond = 91.16°F

LvgEvap = 42.00°F

LIFT = 91.16°F – 42.00°F = 49.16°F

A = 0.00000014592 x (49.16) [4] - 0.0000346496 x (49.16) [3] + 0.00314196 x (49.16) [2] 0.147199 x (49.16) + 3.93073 = 1.02331

B = 0.0015 x 42.00 + 0.934 = 0.99700

Kadj = A x B = 1.02024 FLajd = 0.5600/1.02024 = 0.5489 kW/ton PLVadj = 0.5000/1.02024 = 0.4901 kW/ton

[ASHRAE 90.1:6.4.1.2.1]

For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per

hour = 0.293 kW, 1 gallon per minute = 0.06 L/s, °C = (°F-32)/1.8

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APPENDIX E

E 503.4.1.1 Positive Displacement (air- and water-cooled) Chilling Packages. Equipment with an evaporator leaving fluid temperature higher than 32.00°F (0.00°C) and water-cooled positive displacement chilling packages with a condenser leaving fluid temperature below 115.00°F (46.11°C) shall show compliance with Table E 503.7.1(3) when tested or certified with water at standard rating conditions, in accordance with the referenced test procedure. [ASHRAE 90.1:6.4.1.2.2]

E 503.4.2 Equipment not Listed. Equipment not listed in the tables referenced in Section E 503.4 and Section E 503.4.1 shall be permitted to be used. [ASHRAE 90.1:6.4.1.4]

E 503.4.3 Verification of Equipment Efficiencies. Equipment efficiency information supplied by manufacturers shall be verified in accordance with one of the following:

(1) Equipment covered under EPACT shall be in accordance with U.S. Department of Energy certification requirements.

(2) Where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, then the product shall be listed in the certification program.

(3) Where a certification program exists for a covered product, and it includes provisions for verification and challenge of equipment efficiency ratings, but the product is not listed in the existing certification program, the ratings shall be verified by an independent laboratory test report.

(4) Where no certification program exists for a covered product, the equipment efficiency ratings shall be supported by data furnished by the manufacturer.

(5) Where components such as indoor or outdoor coils from different manufacturers are used, the system designer shall specify component efficiencies whose combined efficiency is in accordance with the minimum equipment efficiency requirements in Section E 503.4 through Section E 503.4.4.1. [ASHRAE 90.1:6.4.1.5]

E 503.4.4 Mechanical Equipment Labeling. Mechanical equipment that is not covered by the U.S. National Appliance Energy Conservation Act (NAECA) of 1987 shall carry a permanent label installed by the manufacturer stating that the equipment is in accordance with the requirements of ASHRAE 90.1. [ASHRAE 90.1:6.4.1.6.1]

E 503.4.4.1 Packaged Terminal Air Condi- tioners. Nonstandard-size packaged terminal air conditioners and heat pumps with existing sleeves having an external wall opening of less than 16 inches (406 mm) high or less than 42 inches (1067 mm) wide and having a cross-sectional area less than 670 square inches (0.432 m [2] ) shall be factory labeled as follows:

Manufactured for nonstandard-size applications only: Not to be installed in new construction projects. [ASHRAE 90.1:6.4.1.6.2]

E 503.4.5 Load Calculations. Heating and cooling system design loads for the purpose of sizing systems and equipment shall be determined in accordance with ASHRAE/ACCA 183. [ASHRAE 90.1:6.4.2.1]

E 503.4.5.1 Pump Head. Pump differential pressure (head) for the purpose of sizing pumps shall be determined in accordance with generally accepted engineering standards and handbooks acceptable to the Authority Having Jurisdiction. The pressure drop through each device and pipe segment in the critical circuit at design conditions shall be calculated.

[ASHRAE 90.1:6.4.2.2]

E 503.4.6 Zone Thermostatic Controls. The supply of heating and cooling energy to each zone shall be individually controlled by thermostatic controls responding to temperature within the zone. For the purposes of Section E 503.4.6, a dwelling unit shall be permitted to be considered a single zone.

Exceptions: Independent perimeter systems that are designed to offset only building envelope loads shall be permitted to serve one or more zones also served by an interior system, provided that:

(1) the perimeter system includes not less than one thermostatic control zone for each building exposure having walls facing only one orientation for 50 contiguous feet (15 240 mm) or more and

(2) the perimeter system heating and cooling supply is controlled by thermostatic controls located within the zones served by the system.

Exterior walls and semiexterior walls are considered to have different orientations where the exposures they face differ by more than 45 degrees (0.79 rad).

[ASHRAE 90.1:6.4.3.1.1]

E 503.4.6.1 Dead Band. Where used to control both heating and cooling, zone thermostatic controls shall be capable of and configured to provide a temperature range or dead band of not less than 5°F (3°C) within which the supply of heating and cooling energy to the zone is shut off or reduced to a minimum.

Exceptions:

(1) Thermostats that require manual changeover between heating and cooling modes.

(2) Special occupancy or special applications where wide temperature ranges are not acceptable (such as retirement homes, process applications, museums, some areas of hospitals) and are approved by the Authority Having Jurisdiction. [ASHRAE 90.1:6.4.3.1.2]

E 503.4.6.2 Setpoint Overlap Restriction. Where heating and cooling to a zone are controlled by separate zone thermostatic controls located within

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APPENDIX E

the zone, means (such as limit switches, mechanical stops, or, for DDC systems, software programming) shall be provided to prevent the heating setpoint from exceeding the cooling setpoint minus any applicable proportional band. [ASHRAE 90.1:6.4.3.2] E 503.4.6.3 Off-Hour Controls. HVAC systems shall have the off-hour controls required by Section E 503.4.6.3.1 through Section E 503.4.6.3.5.

Exceptions:

(1) HVAC systems intended to operate continuously.

(2) HVAC systems not serving residential spaces and having a design heating capacity and cooling capacity less than 7000 Btu/h (2.1 kW) that are equipped with a readily accessible manual ON/OFF controls. [ASHRAE 90.1:6.4.3.3]

E 503.4.6.3.1 Automatic Shutdown. HVAC systems shall be equipped with not less than one of the following:

(1) Controls that can start and stop the system under different time schedules for seven different day-types per week, are capable of retaining programming and time setting during loss of power for a period of not less than 10 hours, and include an accessible manual override, or equivalent function, that allows temporary operation of the system for up to 2 hours.

(2) An occupancy sensor that is capable of shutting the system off when no occupant is sensed for a period of up to 30 minutes.

(3) A manually operated timer capable of being adjusted to operate the system for up to 2 hours.

(4) An interlock to a security system that shuts the system off when the security system is activated.

Exceptions:

(1) Systems serving residential occupancies with controls that can start and stop the system under at least two different time schedules per week.

(2) Systems serving non-residential occupancies where heating or cooling capacity is less than 15 000 Btu/h (4.4 kW) with controls that can start and stop the system under not less than 2 different time schedules per week. [ASHRAE 90.1:6.4.3.3.1] E 503.4.6.3.2 Setback Controls. Heating systems shall be equipped with controls capable of and configured to automatically restart and temporarily operate the system as required to maintain zone temperatures above an adjustable heating setpoint of not less than 10°F (6°C) below the occupied heating setpoint. Cooling systems shall be equipped with con

trols capable of and configured to automatically restart and temporarily operate the mechanical cooling system as required to maintain zone temperatures below an adjustable cooling setpoint of not less than 5°F (3°C) above the occupied cooling setpoint or to prevent high space humidity levels.

Exception: Radiant heating systems capable of and configured with a setback heating setpoint at not less than 4°F (2°C) below the occupied heating setpoint. [ASHRAE 90.1:6.4.3.3.2] E 503.4.6.3.3 Optimum Start Controls. Individual heating and cooling systems with setback controls and DDC shall have optimum start controls. The control algorithm shall, as a minimum, be a function of the difference between space temperature and occupied set point, the outdoor temperature, and the amount of time prior to scheduled occupancy. Mass radiant floor slab systems shall incorporate floor temperature into the optimum start algorithm.

al heating and cooling systems with setback controls and DDC shall have optimum start controls. The control algorithm shall, as a minimum, be a function of the difference between space temperature and occupied set point, the outdoor temperature, and the amount of time prior to scheduled occupancy. Mass radiant floor slab systems shall incorporate floor temperature into the optimum start algorithm.

Exception: Residential spaces are not required to have optimum start controls. [ASHRAE 90.1:6.4.3.3.3] E 503.4.6.3.4 Zone Isolation. HVAC systems serving zones that are intended to operate or be occupied nonsimultaneously shall be divided into isolation areas. Zones shall be permitted to be grouped into a single isolation area provided it does not exceed 25 000 square feet (2322.6 m [2] ) of conditioned floor area and does not include more than one floor. Each isolation area shall be equipped with isolation devices capable of and configured to automatically shut off the supply of conditioned air and outdoor air to and exhaust air from the area. Each isolation area shall be controlled independently by a device meeting the requirements of Section E 503.4.6.3.1. For central systems and plants, controls and devices shall be provided to allow stable system and equipment operation for any length of time while serving only the smallest isolation area served by the system or plant.

Exceptions: Isolation devices and controls are not required for the following:

(1) Exhaust air and outdoor air connections to isolation zones where the fan system to which they connect is not more than 5000 ft [3] /min (2.3597 m [3] /s).

(2) Exhaust airflow from a single isolation zone of less than 10 percent of the design airflow of the exhaust system to which it

connects.

(3) Zones intended to operate continuously or intended to be inoperative only when all other zones are inoperative. [ASHRAE 90.1:6.4.3.3.4]

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APPENDIX E

E 503.4.6.3.5 Automatic Control of HVAC in Hotel/Motel Guest Rooms. Hotels and motels with more than 50 guest rooms shall be provided with automatic controls for the HVAC equipment serving each guest room capable of and configured according to the requirements in Section E 503.4.6.3.5.1. [ASHRAE 90.1:6.4.3.3.5]

E 503.4.6.3.5.1 Guest Room HVAC Set-Point Control. Within 30 minutes of all occupants leaving the guest room, HVAC set points shall be automatically raised by not less than 4°F (2°C) from the occupant set point in the cooling mode and automatically lowered by at least 4°F (2°C) from the occupant set point in the heating mode. When the guest room is unrented and unoccupied, HVAC set points shall be automatically reset to 80°F (27°C) or higher in the cooling mode and to 60°F (16°C) or lower in the heating mode. Unrented and unoccupied guest rooms shall be determined by either of the following:

(1) The guest room has been continuously unoccupied for up to 16 hours.

(2) A networked guest room control system indicates the guest room is unrented and the guest room is unoccupied for no more than 30 minutes.

Exceptions:

(1) A networked guest room control system shall be permitted to return the thermostat set points to their default occupied set points 60 minutes prior to the time the room is scheduled to be occupied.

(2) Cooling for humidity control shall be permitted during unoccupied periods.

E 503.4.6.4 Stair and Elevator Shaft Vent Dampers. Where stair and elevator shafts have vents, they shall be equipped with motorized dampers that are capable of and configured to automatically close during normal building operation and are interlocked to only open as required by fire and smoke detection systems, or by thermostatic control systems.

Exception: Nonmotorized gravity back draft dampers are acceptable in buildings less than three stories in height and for buildings of any height located in Climate Zones 0, 1, 2, and 3. [ASHRAE 90.1:6.4.3.4.1]

E 503.4.6.4.1 Shutoff Damper Controls. Outdoor air intake and exhaust systems shall be equipped with motorized dampers that will automatically shut when the systems or spaces served are not in use. Outdoor air and exhaust or relief dampers shall be capable of and configured to automatically shut off during preoccupancy building warm-up, cooldown, and setback, except when the supply of outdoor air reduces energy costs or when outdoor air shall

be supplied to comply with the code require ments.

Exceptions:

(1) Nonmotorized (gravity back draft) dampers shall be permitted for exhaust and relief in buildings less than three stories in height and for outdoor air intakes and exhaust and relief dampers in buildings of any height located in Climate Zones 0, 1, 2 and 3. Nonmotorized dampers for outdoor air intakes shall be protected from direct exposure to wind.

(2) Nonmotorized dampers shall be permitted in systems with a design outdoor air intake or exhaust capacity of 300 ft [3] /min (0.142 m [3] /s) or less.

(3) Dampers shall not be required in ventilation or exhaust systems serving unconditioned spaces.

(4) Dampers shall not be required in exhaust systems serving Type 1 kitchen exhaust hoods.

(5) Dampers are not required in systems intended to operate continuously. [ASHRAE 90.1:6.4.3.4.2]

E 503.4.6.4.2 Dampers Leakage. Where outdoor air supply, and exhaust or relief dampers are required in Section E 503.4.6.4, they shall have a maximum leakage rate in accordance with Table E 503.4.6.4.2. [ASHRAE 90.1:6.4.3.4.3]

E 503.4.6.4.3 Ventilation Fan Controls. Fans with motors more than 0.75 hp (0.56 kW) shall have automatic controls in accordance with Section E 503.4.6.3.1 that are capable of and configured to shut off fans when not required.

Exception: HVAC systems intended to operate continuously. [ASHRAE 90.1:6.4.3.4.4]

E 503.4.6.5 Parking Garage Ventilation Sys- tems. Parking garage ventilation systems shall meet all of the following:

(1) Separate ventilation systems and control systems shall be provided for each parking garage section.

(2) Control systems for each parking garage section shall automatically detect and control contaminant levels and shall be capable of and configured to reduce fan airflow to 20 percent or less of design capacity.

(3) The ventilation system for each parking garage section shall have controls and devices that

result in fan motor demand of no more than 30 percent of design wattage at 50 percent of the design airflow.

Exception: Garage ventilation systems serving a single parking garage section having a total ventilation system motor nameplate horsepower (kilowatts)

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APPENDIX E

not exceeding 5 hp (3.7 kW) at fan system design conditions and where the parking garage section has no mechanical cooling or mechanical heating.

[ASHRAE 90.1:6.4.3.4.5] E 503.4.6.6 Heat Pump Auxiliary Heat Con- trol. Heat pumps equipped with internal electric resistance heaters shall have controls that prevent supplemental heater operation where the heating load is capable of being met by the heat pump alone during both steady-state operation and setback recovery. Supplemental heater operation shall be permitted during outdoor coil defrost cycles. Exception: Heat pumps whose minimum efficiency is regulated by U.S. National Appliance Energy Conservation Act (NAECA) and whose ratings are in accordance with the requirements shown in Table E 503.7.1(2) and includes the use of an internal electric resistance heating. [ASHRAE 90.1:6.4.3.5] E 503.4.6.7 Humidification and Dehumidifica- tion Control. Humidification and dehumidification

control shall be in accordance with Section E 503.4.6.7.1 through Section E 503.4.6.7.3. E 503.4.6.7.1 Dehumidification. Humidistatic controls shall not use mechanical cooling to reduce the humidity below the lower of a dew point of 55°F (12.8°C) or relative humidity of 60 percent in the coldest zone served by the system. Exceptions: (1) Lower humidity shall be permitted when operating mechanical cooling for temperature control.

(2) Systems serving zones where specific humidity levels are required, such as museums and hospitals, and approved by the Authority Having Jurisdiction or required by accreditation standards, and where humidistatic controls are capable of and configured to maintain a dead band of at least 10 percent relative humidity where no active humidification or dehumidification takes place.

(3) Systems serving zones where humidity levels are required to be maintained with precision of not more than ±5 percent relative humidity to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction.

[ASHRAE 90.1:6.4.3.6.1]

E 503.4.6.7.2 Humidification. Humidistatic controls shall not use fossil fuel or electricity to produce relative humidity above 30 percent in the warmest zone served by the system.

Exceptions:

(1) Systems serving zones where specific humidity levels are required, such as museums and hospitals, and approved by the Authority Having Jurisdiction or required by accreditation standards, and where humidistatic controls are capable of and configured to maintain a dead band of at least 10 percent relative humidity where no active humidification or dehumidification takes place.

TABLE E 503.4.6.4.2 MAXIMUM DAMPER LEAKAGE [1, 2]

(cubic foot per minute per square foot) at 1.0 inch water gauge

[ASHRAE 90.1: TABLE 6.4.3.4.3]

For SI units: 1 square foot = 0.0929 m [2], 1 cubic foot per minute = 0.00047 m [3] /s, 1 cubic foot per minute = 0.4719 L/s, 1 cubic foot per minute per square foot = 5.08 [(L/s)/m [2] ], 1 inch water gauge = 0.249 kPa

Notes:

1 When tested in accordance with AMCA 500D.

2 Dampers smaller than 12 inches (305 mm) in height, width, or diameter need not be tested but shall be of the same design and construction as the smallest tested damper meeting the listed leakage rate requirement.

3 Nonmotorized dampers smaller than 24 inches (610 mm) in height, width, or diameter shall be permitted to have a leakage rate of 40 CFM/ft 2 [0.203 (m 3 /s)/m 2 ].

4 Where permitted by Section E 503.4.6.4.1, exception 2.

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APPENDIX E

(2) Systems serving zones where humidity levels are required to be maintained with precision of not more than ±5 percent relative humidity to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction.

[ASHRAE 90.1:6.4.3.6.2]

E 503.4.6.7.3 Control Interlock. Where a zone is served by a system or systems with both humidification and dehumidification capability, means (such as limit switches, mechanical stops, or, for DDC systems, software programming) shall be provided capable of and configured to prevent simultaneous operation of humidification and dehumidification equipment. Exception: Systems serving zones where humidity levels are required to be maintained with precision of not more than ± 5 percent relative humidity to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction. [ASHRAE 90.1:6.4.3.6.3]

ded capable of and configured to prevent simultaneous operation of humidification and dehumidification equipment. Exception: Systems serving zones where humidity levels are required to be maintained with precision of not more than ± 5 percent relative humidity to comply with applicable codes or accreditation standards or as approved by the Authority Having Jurisdiction. [ASHRAE 90.1:6.4.3.6.3]

E 503.4.6.8 Freeze Protection and Snow or Ice Melting Systems. Freeze protection systems, such as heat tracing of outdoor piping and heat exchangers, including self-regulating heat tracing, shall include automatic controls capable of and configured to shut off the systems when outdoor air temperatures are more than 40°F (4°C) or when the conditions of the protected fluid will prevent freezing. Snow and ice melting systems shall include automatic controls capable of and configured to shut off the systems when the pavement temperature is more than 50°F (10°C) and no precipitation is falling, and an automatic or manual control that will allow shutoff when the outdoor temperature is more than 40°F (4°C) so that the potential for snow or ice accumulation is negligible. [ASHRAE 90.1:6.4.3.7] E 503.4.6.9 Ventilation Controls for High- Occupancy Areas. Demand control ventilation (DCV) shall be required for spaces that are more than 500 square feet (46.45 m [2] ) and with a design occupancy for ventilation of not less than 25 people per 1000 square feet (92.9 m [2] ) of floor area and served by systems with one or more of the following: (1) Air-economizer. (2) Automatic modulating control of outdoor air damper. (3) Design outdoor airflow more than 3000 ft [3] /min (1.4158 m [3] /s). Exceptions: (1) Systems with exhaust air energy recovery in accordance with Section E 503.5.10.1.

(2) Multiple-zone systems without DDC of individual zones communicating with a central control panel. (3) Systems with a design outdoor airflow less than 750 ft [3] /min (0.3540 m [3] /s).

(4) Spaces where more than 75 percent of the space design outdoor airflow is required for makeup air that is exhausted from the space or transfer air that is required for makeup air that is exhausted from other spaces.

(5) Spaces with one of the following occupancy categories in accordance with Chapter 4 or ASHRAE 62.1: correctional cells, daycare sickrooms, science labs, barbers, beauty and nail salons, and bowling alley seating. [ASHRAE 90.1:6.4.3.8]

E 503.4.6.10 Outdoor Heating. Radiant heat systems shall be used to provide heat outdoors. Outdoor radiant heating systems shall be provided with controls that sense the presence of occupants or other device that automatically shuts down the system where no occupants are in the heating area.

E 503.4.6.11 Heated or Cooled Vestibules or Air Curtains with Integral Heating. Heating systems for vestibules and air curtain units with integral heating shall include automatic controls capable of and configured to shut off the heating system when outdoor air temperatures are more than 45°F (7.2°C). Vestibule heating and cooling systems shall be controlled by a thermostat in the vestibule capable of and configured to limit heating to a maximum of 60°F (15.5°C) and cooling to a minimum of 85°F (29.4°C).

Exception: Heating or cooling provided by siterecovered energy or by transfer air that would otherwise be exhausted. [ASHRAE 90.1:6.4.3.9]

E 503.4.6.11.1 Air Curtains. Air curtain unit performance shall be tested in accordance with ANSI/AMCA 220 and shall have a jet speed of not less than 6.6 feet per second (2.0 m/s) at 6 inches (152 mm) above the floor. Automatic controls shall be provided that will operate the air curtain unit with the opening and closing of the door and comply with Section E 503.4.6.11. To ensure proper operation, each air curtain unit shall be commissioned in accordance with the manufacturer’s instructions, including airstream split location and direction. [ASHRAE 90.1:10.4.5] E 503.4.6.12 Direct Digital Control (DDC) Requirements. Direct digital control shall be required in accordance with Section E 503.4.6.12.1 through Section E 503.4.6.12.3. [ASHRAE 90.1:6.4.3.10]

E 503.4.6.12.1 DDC Applications. DDC shall be provided in the applications and qualifications in accordance with Table E 503.4.6.12.1.

Exception : DDC is not required for systems using the simplified approach to compliance in accordance with Section E 503.3. [ASHRAE 90.1:6.4.3.10.1]

E 503.4.6.12.2 DDC Controls. Where DDC is required by Section E 503.4.6.12.1, the DDC

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APPENDIX E

system shall be capable of and configured with all of the following, as required, to provide the control logic required in Section E 503.5:

(1) Monitoring zone and system demand for fan pressure, pump pressure, heating, and cooling.

(2) Transferring zone and system demand information from zones to air distribution system controllers and from air distribution systems to heating and cooling plant controllers.

(3) Automatically detecting those zones and systems that are capable of excessively driving the reset logic and generate an alarm or other indication to the system operator.

(4) Readily allowing operator removal of zone(s) from the reset algorithm. [ASHRAE 90.1:6.4.3.10.2]

E 503.4.6.12.3 DDC Display. Where DDC is required in accordance with Section E 503.4.6.12.1 for new buildings, the DDC system shall be capable of trending and graphically displaying input and output points. [ASHRAE 90.1:6.4.3.10.3]

E 503.4.6.13 Economizer Fault Detection and Diagnostics (FDD). Air-cooled direct-expansion cooling units listed in Tables E 503.7.1(1) and E 503.7.1(2), where an air economizer is installed in accordance with Section E 503.5, shall include a fault detection and diagnostics (FDD) system complying with the following:

(1) The following temperature sensors shall be permanently installed to monitor system operation:

(a) Outdoor air

(b) Supply air

(c) Return air, where required for economizer control

(2) The system shall have the capability of displaying the value of each sensor.

(3) The FDD system or unit controls shall be capable of and configured to provide system status by indicating the following:

(a) Free cooling available

(b) Economizer enabled

(c) Compressor enabled

(d) Heating enabled

(e) Mixed-air low-limit cycle active

(4) The FDD system or unit controls shall have provisions to manually initiate each operating mode so that the operation of compressors, economizers, fans, and the heating system can be independently tested and verified.

(5) The FDD system shall be capable of and configured to detect the following faults:

(a) Air temperature sensor failure/fault

(b) Not economizing when the unit should be economizing

(c) Economizing when the unit should not be economizing

(d) Damper not modulating

(e) Excess outdoor air

(6) The FDD system shall be capable of and configured to report faults to a fault management appli

TABLE E 503.4.6.12.1

DDC APPLICATIONS AND QUALIFICATIONS

[ASHRAE 90.1:6.4.3.10.1]

For SI units: 1000 British thermal units = 0.293 kW, 1 horsepower = 0.746 kW

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APPENDIX E

cation or DDC system accessible by operating or service personnel, or annunciated locally on zone thermostats. [ASHRAE 90.1:6.4.3.12]

E 503.4.7 HVAC System Construction and Insu- lation. HVAC Ducts shall be constructed in accordance with provisions contained in the SMACNA HVAC Duct Construction Standard. HVAC system construction and insulation shall comply with Section E 503.4.7.1 and Section E 503.4.7.2.1.

E 503.4.7.1 Insulation. Insulation required by this section shall be installed in accordance with industry-accepted standards. These requirements shall not apply to HVAC equipment. Insulation shall be protected from damage, including that due to sunlight, moisture, equipment maintenance, and wind, but not limited to the following:

(1) Insulation exposed to weather shall be suitable for outdoor service (e.g., protected by aluminum, sheet metal, painted canvas, or plastic cover). Cellular foam insulation shall be protected as above or painted with a coating that is water retardant and provides shielding from solar radiation that can cause degradation of the material.

(2) Insulation covering chilled-water piping, refrigerant suction piping, or cooling ducts located outside the conditioned space shall include a vapor retardant located outside the insulation (unless the insulation is inherently vapor retardant), all penetrations and joints of which shall be sealed. [ASHRAE 90.1:6.4.4.1.1]

E 503.4.7.1.1 Duct and Plenum Insula- tion. Supply and return ducts and plenums installed as part of an HVAC air distribution system shall be thermally insulated in accordance with Table E 503.7.2.

Exceptions:

(1) Factory-installed plenums, casings, or ductwork furnished as a part of HVAC equipment tested and rated in accordance with Section E 503.4 through Section E 503.4.4.1.

(2) Ducts or plenums located in heated spaces, semi-heated spaces, or cooled spaces.

(3) For runouts less than 10 feet (3048 mm) in length to air terminals or air outlets, the rated R-value of insulation shall not be required to exceed R-3.5.

(4) Backs of air outlets and outlet plenums exposed to unconditioned space or indirectly conditioned space with face areas exceeding 5 square feet (0.5 m [2] ) shall not be required to exceed R-2; those not exceeding 5 square feet (0.5 m [2] ) shall not be required to be insulated. [ASHRAE 90.1:6.4.4.1.2]

E 503.4.7.1.2 Piping Insulation. Piping shall be thermally insulated in accordance with Table E 503.7.3(1) and Table E 503.7.3(2).

Exceptions:

(1) Factory-installed piping within HVAC equipment tested and rated in accordance with Section E 503.4 through Section E 503.4.4.1.

(2) Piping that conveys fluids having a design operating temperature range between 60°F (16°C) and 105°F (41°C), inclusive.

(3) Piping that conveys fluids that have not been heated or cooled through the use of fossil fuels or electricity (such as roof and condensate drains, domestic cold water supply, and natural gas piping).

(4) Where heat gain or heat loss will not increase energy use (such as liquid refrigerant piping).

(5) In piping 1 inch (25.4 mm) or less, insulation is not required for strainers, control valves, and balancing valves. [ASHRAE 90.1:6.4.4.1.3]

E 503.4.7.1.3 Sensible Heating Panel Insu- lation. Thermally ineffective panel surfaces of sensible heating panels, including U-bends and headers, shall be insulated with a minimum of R-3.5. Adjacent building envelope insulation counts toward this requirement. [ASHRAE 90.1:6.4.4.1.4]

E 503.4.7.1.4 Radiant Floor Heating. The bottom surfaces of floor structures incorporating radiant heating shall be insulated with a minimum of R-3.5. Adjacent building envelope insulation counts toward this requirement.

Exception: Heated slab-on-grade floors incorporating radiant heating shall be in accordance with ASHRAE 90.1. [ASHRAE 90.1:6.4.4.1.5]

E 503.4.7.2 Ductwork and Plenum Leakage. Transverse joints, longitudinal seams, and duct wall penetrations shall be sealed. Pressure-sensitive tape shall not be used as the primary sealant, unless it has been certified to comply with UL 181A or UL 181B by an independent testing laboratory and the tape is used in accordance with that certification. All other connections shall be considered transverse joints, including but not limited to spin-ins, taps, other branch connections, access door frames and jambs, and duct connections to equipment.

Exceptions:

(1) Rods that penetrate the duct wall that shall be permitted to move in order to function properly (control rod for volume damper) shall not be sealed in a fashion that prevents them from working properly.

(2) Spiral lock seams in a round or flat oval duct.

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APPENDIX E

E 503.4.7.2.1 Duct Leakage Tests. Ductwork shall be leak-tested in accordance with the SMACNA HVAC Air Duct Leakage Test Manual. Representative sections totaling not less than 20 percent of the total installed duct area shall be tested. Where the tested 20 percent fail to comply with the requirements of this section, then 40 percent of the total installed duct area shall be tested. Where the tested 40 percent fail to comply with the requirements of this section, then 100 percent of the total installed duct area shall be tested. Sections shall be selected by the building owner or designated representative of the building owner. Positive pressure leakage testing shall be permitted for negative pressure ductwork. The permitted duct leakage shall be not more than the following: Lmax = CLP [0.65] (Equation E 503.4.7.2.1)

Where:

Lmax = maximum permitted leakage, (ft [3] /min)/100 square feet [0.0001 (m [3] /s)/m [2] ] duct surface area.

CL = Six, duct leakage class, (ft [3] /min)/100 square feet [0.0001 (m [3] /s)/m [2] ] duct surface area at 1 inch water column (0.2 kPa).

P = test pressure, which shall be equal to the design duct pressure class rating, inch water column (kPa).

E 503.4.8 Walk-In Coolers and Walk-In Freezers.

Site-assembled or site-constructed walk-in coolers and walk-in freezers shall conform to the following requirements:

(1) Shall be equipped with automatic door closers that firmly close walk-in doors that have been closed to within 1 inch (25.4 mm) of full closure.

Exception: Doors wider than 45 inches (1143 mm) or taller than 7 feet (2134 mm).

(2) Doorways shall have strip doors (curtains), springhinged doors, or other method of minimizing infiltration when doors are open.

(3) Walk-in coolers shall contain wall, ceiling, and door insulation of at least R-25 and at least R-32 for walk in freezers.

Exception: Glazed portions of doors or structural members.

(4) Walk-in freezers shall contain floor insulation of at least R-28.

(5) Evaporator fan motors that are less than 1 hp (0.7 kW) and less than 460 V shall use electronically commutated motors (brushless direct-current motors) or three-phase motors.

(6) Lights shall use light sources with an efficacy of 40 lm/W or more, including ballast losses (if any).

Light sources with lower may be used in conjunction with a timer or device that turns off the lights within 15 minutes of when the walk-in cooler or walk-in freezer is not occupied by people.

(7) Transparent reach-in doors for walk-in freezers, and windows in walk-in freezer doors, shall be of triplepane glass, either filled with inert gas or with heatreflective treated glass or vacuum insulating glazing.

(8) Transparent reach-in doors for walk-in coolers, and windows in walk-in cooler doors, shall be doublepane glass with heat-reflective treated glass and gas filled, or triple-pane glass, either filled with inert gas or with heat-reflective treated glass or vacuum insulating glazing.

(9) Antisweat heaters without antisweat heater controls shall have a total door rail, glass, and frame heater power draw of not more than 7.1 W/ft [2] (76 W/m [2] ) of door opening for walk-in freezers and 3.0 W/ft² (32 W/m [2] ) of door opening for walk-in coolers.

(10)Antisweat heater controls shall reduce the energy use of the antisweat heater as a function of the rela tive humidity in the air outside the door or to the condensation on the inner glass pane.

(11)Condenser fan motors that are less than 1 hp (0.7 kW) shall use electronically commutated motors, permanent split-capacitor-type motors, or threephase motors.

(12)All walk-in freezers shall incorporate temperaturebased defrost termination control with a time limit

default. The defrost cycle shall terminate first on an upper temperature limit breach and second upon a time limit breach.

Exception: Walk-in coolers and walk-in freezers combined in a single enclosure greater than 3000 ft² (279 m²).

(13)Doors in walk-in coolers and walk-in freezers shall meet the requirements of ASHRAE 90.1. Walk-in cooler and walk-in freezer refrigeration systems, except for walk-in process cooling refrigeration systems as defined in 10 CFR 431.302, shall meet the requirements of ASHRAE 90.1. [ASHRAE 90.1:6.4.5]

E 503.4.9 Liquid-to-Liquid Heat Exchangers. Plate-type liquid-to-liquid heat exchangers shall be rated in accordance with AHRI 400. [ASHRAE 90.1:6.4.7]

E 503.5 Prescriptive Compliance Path, Economizers. Each cooling system shall include either an air economizer or fluid economizer in accordance with Section E 503.5.1

through Section E 503.5.4.1.

Exceptions: Economizers shall not be required for the following systems:

(1) Individual fan-cooling units with a supply capacity less than the minimum listed in Table E 503.5(1).

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APPENDIX E

TABLE E 503.5(1) MINIMUM FAN-COOLING UNIT SIZE

WHERE AN ECONOMIZER IS REQUIRED

[ASHRAE 90.1: TABLE 6.5.1-1]

For SI units: 1000 British thermal units per hour = 0.293 kW

(2) Chilled-water cooling systems without a fan or that use induced airflow, where the total capacity of these systems is less than 1 000 000 Btu/h (293 kW) in Climate Zones 0, 1B, and 2 through 4; less than 1 400 000 Btu/h (410 kW) in Climate Zones 5 through 8; or any size in Climate Zone 1A.

TABLE E 503.5(2) ELIMINATE REQUIRED ECONOMIZER FOR COMFORT

COOLING BY INCREASING COOLING EFFICIENCY

[ASHRAE 90.1: TABLE 6.5.1-2]

Notes:

1 If a unit is rated with an annualized or part-load metric IPLV, IEER, or SEER, then to eliminate the required economizer, only the annualized or part-load minimum cooling efficiency of the HVAC unit must be increased by the percentage shown. Where the HVAC unit is rated with a full load metric like EER cooling, these shall be increased by the percentage shown. To determine the efficiency required to eliminate the economizer when the unit equipment efficiency is rated with an energy-input divided by a thermal-output metric, the metric shall first be converted to COP by the efficiency improvement percentage shown. The COP shall then be converted back to the original rated metric to establish the efficiency required to eliminate the economizer.

2 Some examples of annualized or part-load metrics are: IPLV.IP, IEER,

and SEER.

(3) Systems that include nonparticulate air treatment in accordance with ASHRAE 62.1.

(4) In hospitals and ambulatory surgery centers, where more than 75 percent of the air designed to be supplied by the system is to spaces that are required to be humidified more than 35°F (2°C) dew-point temperature to comply with applicable codes or accreditation standards; in all other buildings, where more than 25 percent of the air designed to be supplied by the system is to spaces that are designed to be humidified more than 35°F (2°C) dewpoint temperature to satisfy process application needs. This exception shall not apply to computer rooms. (5) Systems that include a condenser heat recovery system with a minimum capacity in accordance with Section E 503.5.10.2.2.

(6) Systems that serve residential spaces where the system capacity is less than five times the requirement listed in Table E 503.5(1). (7) Systems that serve spaces whose sensible cooling load at design conditions, excluding transmission and infiltration loads, is less than or equal to transmission and infiltration losses at an outdoor temperature of 60°F (16°C).

(8) Systems expected to operate less than 20 hours per week.

(9) Where the use of outdoor air for cooling will affect supermarket open refrigerated casework systems.

(10)For comfort cooling where the cooling efficiency is not less than the efficiency improvement requirements in accordance with Table E 503.5(2).

(11)Systems primarily serving computer rooms where in accordance with one of the following:

(a) The total design cooling load of all computer rooms in the building is less than 3 000 000 Btu/h (879 kW) and the building in which they are located is not served by a centralized chilled water plant.

(b) The room total design cooling load is less than 600 000 Btu/h (176 kW) and the building in which they are located is served by a centralized chilled water plant.

(c) The local water authority does not permit cooling

towers.

(d) Less than 600 000 Btu/h (176 kW) of computer room cooling equipment capacity is being added to an existing building.

(12)Dedicated systems for computer rooms where a minimum of 75 percent of the design load serves one of the following:

(a) Spaces classified as an essential facility.

(b) Spaces having a design of Tier IV in accordance with TIA 942.

(c) Spaces classified as Critical Operations Power Systems (COPS) in accordance with NFPA 70.

(d) Spaces where core clearing and settlement services are performed such that their failure to settle pending financial transactions is capable of systemic risk

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APPENDIX E

in accordance with “The Interagency Paper on Sound Practices to Strengthen the Resilience of the US Financial System” (April 7, 2003). [ASHRAE 90.1:6.5.1]

E 503.5.1 Air Economizers, Design Capacity. Air economizer systems shall be capable of and configured to modulate outdoor air and return air dampers to provide up to 100 percent of the design supply air quantity as outdoor air for cooling. [ASHRAE 90.1:6.5.1.1.1]

E 503.5.1.1 Control Signal. Economizer controls shall be capable of and configured to sequence the dampers with the mechanical cooling equipment and shall not be controlled by only mixed air temperature.

Exception: The use of mixed air temperature limit control shall be permitted for systems controlled from space temperature (such as single-zone systems). [ASHRAE 90.1:6.5.1.1.2]

E 503.5.1.2 High-Limit Shutoff. Air economizers shall be capable of and configured to automatically reduce outdoor air intake to the design minimum outdoor air quantity where outdoor air intake will no longer reduce cooling energy use. High-limit shutoff control types and associated setpoints for specific climate zones shall be chosen from Table E

503.5.1.2. [ASHRAE 90.1:6.5.1.1.3]

E 503.5.1.3 Dampers. Exhaust or relief, and outdoor air dampers shall meet the requirements of Table E 503.4.6.4.2. Return dampers shall meet the requirements of motorized exhaust or relief dampers in Table E 503.4.6.4.2.

Exception: Exhaust or relief and outdoor air intake dampers on systems intended to operate continuously. [ASHRAE 90.1:6.5.1.1.4]

E 503.5.1.4 Relief of Excess Outdoor Air.

Relief of excess outdoor air shall be in accordance in accordance with the following:

(1) Systems shall provide one of the following means to relieve excess outdoor air during air economizer operation to prevent overpressurizing the building:

(a) Return or relief fan(s) meeting the requirements of Section E 503.5.6.2.3.

(b) Barometric or motorized damper relief path with a total pressure drop at design relief airflow rate less than 0.10 inches of water

(25 Pa) from the occupied space to outdoors. Design relief airflow rate shall be the design supply airflow rate minus any continuous exhaust flows, such as toilet exhaust fans, whose makeup is provided by the economizer system.

(2) The relief air outlet shall be located so as to avoid recirculation into the building. [ASHRAE 90.1:6.5.1.1.5]

E 503.5.1.5 Sensor Accuracy. Outdoor air, return air, mixed air, and supply air sensors shall be calibrated within the following accuracies:

(1) Dry-bulb and wet-bulb temperatures shall be accurate to ±2°F (1.1°C) over the range of 40°F (4.4°C) to 80°F (27°C).

TABLE E 503.5.1.2

HIGH-LIMIT SHUTOFF CONTROL SETTINGS FOR AIR ECONOMIZERS [2]

[ASHRAE 90.1: TABLE 6.5.1.1.3]

For SI units: °C = (°F-32)/1.8, 1 British thermal unit per pound = 2326 J/kg Notes: 1 At altitudes substantially different than sea level, the fixed enthalpy limit shall be set to the enthalpy value at 75°F (24°C) and 50 percent relative humidity. As an example, at approximately 6000 feet (1829 m) elevation, the fixed enthalpy limit shall be approximately 30.7 Btu/lb (71 408 J/kg). 2 Devices with selectable rather than adjustable setpoints shall be capable of being set to within 2°F (1°C) and 2 Btu/lb (4649 J/kg) of the setpoint listed.

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APPENDIX E

(2) Enthalpy and the value of a differential enthalpy sensor shall be accurate to ±3 Btu/lb (7 E+03 J/kg) over the range of 20 Btu/lb (4.6 E+04 J/kg) to 36 Btu/lb (8.4 E+04 J/kg).

(3) Relative humidity shall be accurate to ±5 percent over the range of 20 percent to 80 percent relative humidity. [ASHRAE 90.1:6.5.1.1.6]

E 503.5.2 Fluid Economizers, Design Capacity. Fluid economizer systems shall be capable of providing up to 100 percent of the expected system cooling load at outdoor air temperatures of not more than 50°F (10°C) dry-bulb or 45°F (7°C) wet-bulb.

Exceptions:

(1) Systems primarily serving computer rooms in which 100 percent of the expected system cooling load at the dry-bulb and wet-bulb temperatures in accordance with Table E 503.5.2 is met with water-cooled

fluid economizers.

(2) Systems primarily serving computer rooms in which 100 percent of the expected system cooling load at the dry-bulb temperatures listed in Table E 503.5.2 is met with air-cooled fluid economizers.

(3) Systems where dehumidification requirements are not capable of being met using outdoor air temper

atures of 50°F (10°C) dry-bulb or 45°F (7°C) wetbulb and where 100 percent of the expected system cooling load at 45°F (7°C) dry-bulb or 40°F (4°C) wet-bulb is met with water-cooled fluid economiz ers. [ASHRAE 90.1:6.5.1.2.1]

E 503.5.2.1 Maximum Hydronic Pressure Drop. Precooling coils and fluid-to-water heat exchangers used as part of a fluid economizer system shall either have a water-side pressure drop of less than 15 feet of water (45 kPa), or a secondary loop shall be created so that the coil or heat exchanger pressure drop is not seen by the circulating pumps where the system is in the normal cooling (non-economizer) mode. [ASHRAE 90.1:6.5.1.2.2]

E 503.5.3 Integrated Economizer Control. Economizer systems shall be integrated with the mechanical cooling system and be capable of and configured to provide partial cooling even where additional mechanical cooling is required to be in accordance with the remainder of the cooling load. Controls shall not false load the mechanical cooling systems by limiting or disabling the economizer or by other means, such as hot gas bypass, except at the lowest stage of mechanical cooling.

Units that include an air economizer shall comply with the following:

TABLE E 503.5.2

FLUID ECONOMIZER SIZING DRY-BULB AND WET-BULB REQUIREMENTS FOR COMPUTER ROOMS*

[ASHRAE 90.1: TABLE 6.5.1.2.1]

For SI units: °C = (°F-32)/1.8

• NR = Not Required

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APPENDIX E

(1) Unit controls shall have the mechanical cooling capacity control interlocked with the air economizer controls such that the outdoor air damper is at the 100 percent open position when mechanical cooling is on, and the outdoor air damper does not begin to close to prevent coil freezing due to minimum compressor run time until the leaving air temperature is less than 45°F (7°C).

(2) DX units with a rated capacity no less than 65 000 Btu/h (19 kW) that control the capacity of the mechanical cooling directly based on occupied space temperature shall have not less than two stages of mechanical cooling capacity.

(3) Other DX units, including those that control space temperature by modulating the airflow to the space, shall comply with the requirements of Table E 503.5.3. [ASHRAE 90.1:6.5.1.3]

been previously cooled, either by mechanical cooling or by economizer systems.

(4) Other simultaneous operation of heating and cooling systems to the same zone.

Exceptions:

(1) Zones for which the volume of air that is reheated, recooled, or mixed is less than the larger of the following:

(a) For systems without DDC, 30 percent of the zone design peak supply.

(b) For systems with DDC, the minimum primary airflow rate required to meet the Simplified Procedure ventilation requirements of Chapter 4 or ASHRAE 62.1 for the zone, permitted to be the average airflow rate as allowed by Chapter 4 or ASHRAE 62.1.

(c) Any higher rate that can be demonstrated, to the satisfaction of the Authority Having Jurisdiction, to reduce overall system annual energy use by offsetting reheat/recool energy losses through a reduction in outdoor air intake for the system.

(d) The airflow rate required to be in accordance with applicable codes or accreditation standards, such as pressure relationships or minimum air change rates.

(2) Zones with DDC that comply with the following:

(a) The airflow rate in dead band between heating and cooling does not exceed the larger of the following:

(i) The minimum primary airflow rate required to meet the Simplified Procedure ventilation requirements of Chapter 4 or ASHRAE 62.1 for the zone, permitted to be the average airflow rate as allowed by Chapter 4 or ASHRAE 62.1.

(ii) A higher rate that can be demonstrated, to the satisfaction of the Authority Having Jurisdiction, to reduce overall system annual energy use by offsetting reheat/recool energy losses through a reduction in outdoor air intake.

(iii) The airflow rate required with applicable codes or accreditation standards, such as pressure relationships or minimum air change rates.

(b) The airflow rate that is reheated, recooled, or mixed shall be less than 50 percent of the zone design peak supply rate.

(c) The first stage of heating consists of modulating the zone supply air temperature set

TABLE E 503.5.3

DX COOLING STAGE REQUIREMENTS FOR

MODULATING AIRFLOW UNITS

[ASHRAE 90.1: TABLE 6.5.1.3]

For SI units: 1000 British thermal units = 0.293 kW

• For mechanical cooling stage control that does not use variable compressor displacement the percent displacement shall be equivalent to the mechanical cooling capacity reduction evaluated at the full load rating conditions for the compressor.

E 503.5.4 Economizer Heating System Impact. HVAC system design and economizer controls shall be such that economizer operation does not increase the building heating energy use during normal operation.

Exception: Economizers on variable air valve (VAV) systems that cause zone level heating to increase due to a reduction in supply air temperature. [ASHRAE 90.1:6.5.1.4] E 503.5.4.1 Economizer Humidification Sys- tem Impact. Systems with hydronic cooling and humidification systems designed to maintain inside humidity at a dew-point temperature more than 35°F (2°C) shall use a fluid economizer where an economizer is required in accordance with Section E 503.5 through Section E 503.5.4.1. [ASHRAE 90.1:6.5.1.5] E 503.5.5 Simultaneous Heating and Cooling Limitation, Zone Controls. Zone thermostatic controls shall prevent the following:

(1) Reheating.

(2) Recooling.

(3) Mixing or simultaneously supplying air that has been previously mechanically heated and air that has

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APPENDIX E

point up to a maximum setpoint while the airflow is maintained at the dead band flow

rate.

(d) The second stage of heating consists of modulating the airflow rate from the dead band flow rate up to the heating maximum flow rate.

(3) Laboratory exhaust systems that comply with Section E 503.5.11.3.

(4) Zones where at least 75 percent of the energy for reheating or for providing warm air in mixing systems is provided from site-recovered energy (including condenser heat) or on-site renewable energy. [ASHRAE 90.1:6.5.2.1]

E 503.5.5.1 Supply Air Temperature Reheat Limit. Where reheating is permitted in accordance with this appendix, zones that have both supply and return or exhaust air openings more than 6 feet (1829 mm) above the floor shall not supply heating air more than 20°F (11°C) above the space temperature setpoint.

Exceptions:

(1) Laboratory exhaust systems in accordance with Section E 503.5.11.3.

(2) During preoccupancy building warm-up and setback. [ASHRAE 90.1:6.5.2.1.1]

E 503.5.5.2 Hydronic System Controls. The heating of fluids in hydronic systems that have been previously mechanically cooled and the cooling of fluids that have been previously mechanically heated shall be limited in accordance with Section

E 503.5.5.2.1 through Section E 503.5.5.2.3.

[ASHRAE 90.1:6.5.2.2]

E 503.5.5.2.1 Three-Pipe System. Hydronic systems that use a common return system for both hot water and chilled water shall not be used. [ASHRAE 90.1:6.5.2.2.1]

E 503.5.5.2.2 Two-Pipe Changeover Sys- tem. Systems that use a common distribution system to supply both heated and chilled water are acceptable where in accordance with the following:

(1) The system is designed to allow a dead band between changeover from one mode to the other of not less than 15°F (8°C) outdoor air temperature.

(2) The system is designed to operate and is provided with controls that will allow operation in one mode for not less than 4 hours before changing over to the other mode.

(3) Reset controls are provided that allow heating and cooling supply temperatures at the changeover point to be not more than 30°F (17°C) apart. [ASHRAE 90.1:6.5.2.2.2]

E 503.5.5.2.3 Hydronic (Water Loop) Heat Pump Systems. Hydronic heat pumps connected to a common heat pump water loop with central devices for heat rejection (e.g., cooling tower) and heat addition (e.g., boiler) shall have the following:

(1) Controls that are capable of and configured to provide a heat pump water supply temperature dead band of at least 20°F (11°C) between initiation of heat rejection and heat addition by the central devices (e.g., tower and boiler).

(2) For climate zone 3 through zone 8, where a closed-circuit cooling tower (fluid cooler) is used, either an automatic valve shall be installed to bypass all but a minimal flow of water around the tower (for freeze protection) or low-leakage positive closure dampers shall be provided. Where an opencircuit cooling tower is used directly in the heat pump loop, an automatic valve shall be installed to bypass all heat pump water flow around the tower. Where an open-circuit cooling tower is used in conjunction with a separate heat exchanger to isolate the tower from the heat pump loop then heat loss shall be controlled by shutting down the circulation pump on the cooling tower loop.

Exception: Where a system loop temperature optimization controller is used to determine the most efficient operating temperature based on real-time conditions of demand and capacity, dead bands of less than 20°F (11°C) shall be permitted.

[ASHRAE 90.1:6.5.2.2.3]

E 503.5.5.3 Dehumidification. Where humidity controls are provided, such controls shall prevent reheating, mixing of hot and cold airstreams, or other means of simultaneous heating and cooling of the same airstream.

Exceptions:

(1) The system is capable of and configured to reduce supply air volume to 50 percent or less of the design airflow rate or the minimum outdoor air ventilation rate in accordance with Chapter 4 or ASHRAE 62.1 or other applicable federal, state, or local code or recognized standard, whichever is larger before simultaneous heating and cooling takes place.

(2) The individual fan cooling unit has a design cooling capacity of not more than 65 000 Btu/h (19 kW) and is capable of and configured to unload to 50 percent capacity before simultaneous heating and cooling takes place.

(3) The individual mechanical cooling unit has a design cooling capacity of not more than 40 000

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APPENDIX E

Btu/h (11.7 kW). An individual mechanical cooling unit is a single system composed of a fan or fans and a cooling coil capable of providing mechanical cooling.

(4) Systems serving spaces where specific humidity levels are required to satisfy process application needs, such as vivariums, museums, surgical suites, pharmacies, and buildings with refrigerating systems, such as supermarkets, refrigerated warehouses, and ice arenas, and where the building includes site-recovered energy or on-site renewable energy that provide energy equal to 75 percent or more of the annual energy for reheating or for providing warm air in mixing systems. This exception shall not apply to computer rooms.

(5) Not less than 90 percent of the annual energy for reheating or for providing warm air in mixing systems is provided from site-recovered energy (including condenser heat) or on-site renewable energy.

(6) Systems where the heat added to the airstream is the result of the use of a desiccant system and 75 percent of the heat added by the desiccant system is removed by a heat exchanger, either before or after the desiccant system with energy recovery. [ASHRAE 90.1:6.5.2.3]

E 503.5.5.4 Humidifier Preheat. Humidifiers

with preheating jackets mounted in the airstream shall be provided with an automatic valve to shut off preheat where humidification is not required.

[ASHRAE 90.1:6.5.2.4.1]

E 503.5.5.4.1 Insulation. Humidification system dispersion tube hot surfaces in the airstreams of ducts or air-handling units shall be insulated with a product with an insulating value of not less than R-0.5.

Exception: Systems where mechanical cooling, including economizer operation, does not occur

simultaneously with humidification. [ASHRAE 90.1:6.5.2.4.2]

E 503.5.5.5 Preheat Coils. Preheat coils shall have controls that stop their heat output where mechanical cooling, including economizer operation, is occurring. [ASHRAE 90.1:6.5.2.5]

E 503.5.5.6 Ventilation Air Heating Control. Units that provide ventilation air to multiple zones and operate in conjunction with zone heating and cooling systems shall not use heating or heat recovery to warm supply air above 60°F (16°C) when representative building loads or outdoor air temperature indicate that the majority of zones require cooling.

Exception: Units that heat the airstream using only series energy recovery when representative building loads or outdoor air temperature indicate that the majority of zones require cooling in Climate Zones 0A, 1A, 2A, 3A, and 4A. [ASHRAE 90.1:6.5.2.6]

E 503.5.6 Air System Design and Control. HVAC air system design and control shall be in accordance with the provisions of Section E 503.5.6.1 through Section E 503.5.6.8.

E 503.5.6.1 Fan System Power and Efficiency. Each HVAC system having a total fan system motor nameplate horsepower (kW) exceeding 5 hp (3.7 kW) at fan system design conditions shall not exceed the allowable fan system motor nameplate horsepower (kW) (Option 1) or fan system brake horsepower (kW) (Option 2) as shown in Table E 503.5.6.1(1). This shall include supply fans, return or relief fans, exhaust fans, and fan-powered terminal units associated with systems providing heating or cooling capability that operate at fan system design conditions. Single-zone VAV systems shall comply with the constant-volume fan power limitation.

Exceptions:

(1) Hospital, vivarium, and laboratory systems that utilize flow control devices on exhaust, return, or both to maintain space pressure relationships

TABLE E 503.5.6.1(1) FAN POWER LIMITATION*

[ASHRAE 90.1: TABLE 6.5.3.1-1]

For SI units: 1 horsepower = 0.746 kW, 1 cubic foot per minute = 0.00047 m [3] /s, 1 cubic foot per minute = 0.4719 L/s

• Where:

A = sum of ( PD x CFMD /4131) bhp = the maximum combined fan brake horsepower (kW) CFMD = the design airflow through each applicable device from Table E 503.5.6.1(2) in CFM (m [3] /s) CFMS = the maximum design supply airflow rate to conditioned spaces served by the system in CFM (m [3] /s) hp = the maximum combined motor nameplate horsepower (kW) PD = each applicable pressure drop adjustment from Table E 503.5.6.1(2) in inch water column (kPa)

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APPENDIX E

TABLE E 503.5.6.1(2) FAN POWER LIMITATION PRESSURE DROP ADJUSTMENT

[ASHRAE 90.1: TABLE 6.5.3.1-2]

For SI units: 1 inch water column = 0.249 kPa, 1 foot = 304.8 mm

necessary for occupant health and safety, or environmental control shall be permitted to use variable-volume fan power limitation.

(2) Individual exhaust fans with motor nameplate horsepower of 1 hp (0.7 kW) or less. [ASHRAE 90.1:6.5.3.1.1]

E 503.5.6.1.1 Fan Motor Selection. Fan

motor selection shall be in accordance with the following:

(1) For each fan less than 6 bhp (4.5 kW), the selected fan motor shall be no larger than the first available motor with a nameplate rating greater than 1.5 times the bhp.

(2) For each fan 6 bhp (4.5 kW) and larger, the selected fan motor shall be no larger than the first available motor with a nameplate rating greater than 1.3 times the bhp. The fan bhp must be indicated on the design documents to allow for compliance verification by the Authority Having Jurisdiction.

Exceptions:

(1) Motors equipped with electronic speed control devices to vary the fan airflow as a function of load.

(2) Systems that are in accordance with Section E 503.5.6.1, Option 1.

(3) Fans with motor nameplate horsepower of less than 1 hp (0.7 kW).

(4) Fans with a fan nameplate electrical input power of less than 1.2 hp (0.89 kW).

[ASHRAE 90.1:6.5.3.1.2]

E 503.5.6.1.2 Fan Efficiency. Each fan and fan array shall have a fan energy index (FEI) of 1.00 or higher. Each fan and fan array used for a variable-air-volume system that meets the requirements of Section E 503.5.6.2 shall have an FEI of 0.95 or higher. The FEI for fan arrays shall be calculated in accordance with AMCA

Exceptions:

(1) Fans that are not embedded fans with a motor nameplate horsepower of less than 1 hp (0.7 kW) or with a fan nameplate electrical input power of less than 1.2 hp (0.89 kW).

(2) Embedded fans and fan arrays with a combined motor nameplate horsepower of 5 hp (3.7 kW) or less or with a fan system electrical input power of 5.5 hp (4.1 kW) or less.

(3) Embedded Fans that are part of equipment listed under Section E 503.4.

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APPENDIX E

(4) Embedded fans included in equipment bearing a third-party-certified seal for air or energy performance of the equipment package.

(5) Ceiling fans.

(6) Fans used for moving gases at temperatures above 482°F (250 °C).

(7) Fans used for operation in explosive atmospheres.

(8) Reversible fans used for tunnel ventilation.

(9) Fans outside the scope of AMCA 208.

(10) Fans that are intended to only operate during emergency conditions. [ASHRAE 90.1:6.5.3.1.3] E 503.5.6.2 Supply Fan Airflow Control. Each cooling system listed in Table E 503.5.6.2 shall be designed to vary the supply fan airflow as a function of load and shall comply with the following requirements:

(1) DX and chilled-water cooling units that control the capacity of the mechanical cooling directly based on space temperature shall have a minimum of two stages of fan control. Low or minimum speed shall not exceed 66 percent of full speed. At low or minimum speed, the fan system shall draw no more than 40 percent of the fan power at full fan speed. Low or minimum speed shall be used during periods of low cooling load and ventilation-only operation.

e capacity of the mechanical cooling directly based on space temperature shall have a minimum of two stages of fan control. Low or minimum speed shall not exceed 66 percent of full speed. At low or minimum speed, the fan system shall draw no more than 40 percent of the fan power at full fan speed. Low or minimum speed shall be used during periods of low cooling load and ventilation-only operation.

(2) All other units, including DX cooling units and chilled-water units that control the space temperature by modulating the airflow to the space, shall have modulating fan control. Minimum speed shall not exceed 50 percent of full speed. At minimum speed, the fan system shall draw no more than 30 percent of the power at full fan speed. Low or minimum speed shall be used during periods of low cooling load and ventilation-only operation.

(3) Units that include an air economizer to meet the requirements of Section E 503.5 through Section E 503.5.4.1 shall have a minimum of two speeds of fan control during economizer operation.

Exceptions:

(1) Modulating fan control shall not be required for chilled-water and evaporative cooling units with less than 1 hp (0.7 kW) fan motors where the units are not used to provide ventilation air and where the indoor fan cycles with the load.

(2) Where the volume of outdoor air required to meet the ventilation requirements of Chapter 4 or ASHRAE 62.1 at low speed exceeds the air that would be delivered at the speed defined in Section E 503.5.6.2(1), or Section E 503.5.6.2(2), then the minimum speed shall be selected to provide the required ventilation air.

[ASHRAE 90.1:6.5.3.2.1]

TABLE E 503.5.6.2

FAN AIRFLOW CONTROL

[ASHRAE 90.1: TABLE 6.5.3.2.1]

For SI units: 1000 British thermal units per hour = 0.293 kW, 1 horsepower = 0.746 kW, 1 cubic foot per minute = 0.00047 m [3] /s

E 503.5.6.2.1 VAV Static Pressure Sensor Location. Static pressure sensors used to control VAV fans shall be located such that the controller setpoint is not more than 1.2 inches water column (0.30 kPa). Where this results in the sensor being located downstream of major duct splits, sensors shall be installed in each major branch to ensure that static pressure is maintained in each.

Exception: Systems that are in accordance with Section E 503.5.6.2.2. [ASHRAE 90.1:6.5.3.2.2]

E 503.5.6.2.2 VAV Setpoint Reset. For multiple-zone VAV systems having a total fan system motor nameplate horsepower exceeding 5 hp (3.7 kW) with DDC of individual zones reporting to the central control panel, static pressure setpoint shall be reset based on the zone requiring the most pressure, such as the setpoint is reset lower until one zone damper is nearly wide open. Controls shall provide the following:

(1) Monitor zone damper positions or other indicator of need for static pressure.

(2) Automatically detect those zones that are capable of excessively driving the reset logic and generate an alarm to the system operator.

(3) Readily allow operator removal of zones from the reset algorithm. [ASHRAE 90.1:6.5.3.2.3]

E 503.5.6.2.3 Return and Relief Fan Con-

trol. Return and relief fans used to meet Section E 503.5.1.4 shall comply with all of the following:

(1) Relief air rate shall be controlled to maintain building pressure either directly, or indirectly through differential supplyreturn airflow tracking. Systems with constant speed or multispeed supply fans shall also be allowed to control the relief system based on outdoor air damper position.

(2) Fans shall have variable-speed control or other devices that will result in total return/relief fan system demand of no more than 30 percent of total design power at 50 percent of total design fan flow.

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APPENDIX E

Exceptions:

(1) Return or relief fans with total motor size less than or equal to 0.5 hp (0.37 kW).

(2) Staged relief fans with a minimum of four stages. [ASHRAE 90.1:6.5.3.2.4]

E 503.5.6.3 Multiple-Zone VAV System Venti- lation Optimization Control. Multiple-zone VAV systems with DDC of individual zone boxes reporting to a central control panel shall include means to automatically reduce outdoor air intake flow below design rates in response to changes in system ventilation efficiency in accordance with Section 404.0 or ASHRAE 62.1.

Exceptions:

(1) VAV systems with zonal transfer fans that recirculate air from other zones without directly mixing it with outdoor air, dual-duct dual-fan VAV systems, and VAV systems with fanpowered terminal units.

(2) Systems where total design exhaust airflow is more than 70 percent of total design outdoor air intake flow requirements. [ASHRAE 90.1:6.5.3.3]

E 503.5.6.4 Supply Air Temperature Reset Controls. Multiple zone HVAC systems shall include controls that are capable of and configured to automatically reset the supply air temperature in response to representative building loads, or to outdoor air temperature. The controls shall reset the supply air temperature to at least 25 percent of the difference between the design supply air temperature and the design room air temperature. Controls that adjust the reset based on zone humidity shall be permitted in Climate Zones 0B, 1B, 2B, 3B, 3C, and 4 through 8. HVAC zone that are expected to experience relatively constant loads shall have maximum airflow designed to accommodate the fully reset supply air temperature.

HVAC zones that are expected to experience relatively constant loads typically include electronic equipment rooms and interior zones.

Exceptions:

(1) Systems in Climate Zones 0A, 1A, and 3A with less than 3000 cubic feet per minute (1.4 m [3] /s) of design outdoor air.

(2) Systems in Climate Zone 2A with less than 10 000 cubic feet per minute (4.7 m [3] /s) of design outdoor air.

(3) Systems in Climate Zones 0A, 1A, 2A, and 3A with at least 80 percent outdoor air and employing exhaust air energy recovery complying with Section E 503.5.10.1.

(4) Systems that prevent reheating, recooling, or mixing of heated and cooled supply air.

(5) Systems in which at least 75 percent of the energy for reheating (on an annual basis) is from site recovered energy or on-site renewable energy. [ASHRAE 90.1:6.5.3.5]

E 503.5.6.5 Fractional Horsepower Fan Motors. Motors for fans that are [1] ⁄ 12 hp (62.1 W) or more and less than 1 hp (0.7 kW) shall be electronically-commutated motors or shall have a motor efficiency of not less than 70 percent where rated in accordance with DOE 10 CFR 431. These motors

shall also have the means to adjust motor speed for either balancing or remote control. Belt-driven fans shall be permitted to use sheave adjustments for airflow balancing in lieu of a varying motor speed.

Exceptions:

(1) Motors in the airstream within fan coils and terminal units that operate when providing heating to the space served.

(2) Motors installed in space conditioning equipment certified in accordance with Section E

503.4 through Section E 503.4.4.1.

(3) Motors shown in Table E 503.5.6.5(1) or Table E 503.5.6.5(2). [ASHRAE 90.1:6.5.3.6]

E 503.5.6.6 Low Power Fans. Fans that are not

covered by Section E 503.5.6.5 and having a fan nameplate electrical input power of less than 180 W or having a motor nameplate horsepower less than

1 / 12 hp (62.1 W) shall meet the fan efficacy requirements specified in ASHRAE 90.1. [ASHRAE 90.1:6.5.3.7]

E 503.5.6.7 Ventilation Design. The required minimum outdoor air rate is the larger of the minimum outdoor air rate or the minimum exhaust air rate

required by Chapter 4, ASHRAE 62.1, ASHRAE 62.2, ASHRAE/ASHE 170, or applicable codes or accreditation standards. Outdoor air ventilation systems shall comply with one of the following:

(1) Design minimum system outdoor air provided shall not exceed 135 percent of the required minimum outdoor air rate.

(2) Dampers, ductwork, and controls shall be provided that allow the system to supply no more than the required minimum outdoor air rate with a single setpoint adjustment.

(3) The system includes exhaust air energy recovery complying with Section E 503.5.10.1.

[ASHRAE 90.1:6.5.3.8]

E 503.5.6.8 Occupied-Standby Controls. Zones serving only rooms that are required to have automatic partial OFF or automatic full OFF lighting controls in accordance with ASHRAE 90.1, where the Chapter 4 or ASHRAE 62.1 occupancy category permits ventilation air to be reduced to zero when

«

438 2025 CALIFORNIA MECHANICAL CODE

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APPENDIX E

For SI units: 1 horsepower = 0.746 kW

 - Average full-load efficiencies shall be established in accordance with 10 CFR 431.

TABLE E 503.5.6.5(2) MINIMUM AVERAGE FULL-LOAD EFFICIENCY FOR CAPACITOR-START CAPACITOR-RUN AND

CAPACITOR-START INDUCTION-RUN SMALL ELECTRIC MOTORS*

For SI units: 1 horsepower = 0.746 kW

• Average full-load efficiencies shall be established in accordance with 10 CFR 431.

the space is in occupied-standby mode, and when using the Ventilation Rate Procedure, shall meet the following within 5 minutes of all rooms in that zone entering occupied-standby mode.

(1) Active heating set point shall be setback at least 1°F (0.6°C).

(2) Active cooling set point shall be setup at least 1°F (0.6°C).

(3) All airflow supplied to the zone shall be shut off whenever the space temperature is between the active heating and cooling set points.

Exception: Multiple zone systems without automatic zone flow control dampers.

[ASHRAE 90.1:6.5.3.9]

E 503.5.7 Hydronic System Design and Control. Hydronic system design and control shall be in accordance with Section E 503.5.7.1 and Section E 503.5.7.7.

E 503.5.7.1 Boiler Turndown. Boiler systems with design input of 1 000 000 Btu/h (293 kW) or more shall comply with the turndown ratio in accordance with Table E 503.5.7.

The system turndown requirement shall use multiple single-input boilers, one or more modulating boilers, or a combination of single-input and modulating boilers.

Boilers shall comply with the minimum efficiency requirements in Table E 503.7.1(6).

[ASHRAE 90.1:6.5.4.1]

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APPENDIX E

TABLE E 503.5.7.2

PUMP FLOW CONTROL REQUIREMENTS

[ASHRAE 90.1: TABLE 6.5.4.2]

»

TABLE E 503.5.7

BOILER TURNDOWN

[ASHRAE 90.1: TABLE 6.5.4.1]

For SI units: 1000 British thermal units per hour = 0.293 kW

E 503.5.7.2 Hydronic Variable Flow Systems. Chilled- and hot-water distribution systems that include three or more control valves designed to modulate or step open and close as a function of load shall be designed for variable fluid flow and shall be capable of and configured to reduce pump flow rates to not more than the larger of 25 percent of the design flow rate or the minimum flow required by the heating/cooling equipment manufacturer for the proper operation of equipment. Individual or parallel pumps serving variable-flow heating-water or chilledwater systems, where the nameplate horsepower of the motor or combined parallel motors is not less than the power shown in Table E 503.5.7.2, shall have controls or devices that will result in pump motor demand of not more than 30 percent of design wattage at 50 percent of design water flow. The controls or devices shall be controlled as a function of desired flow or to

maintain a minimum required differential pressure. Differential pressure shall be measured at or near the most remote heat exchanger or the heat exchanger requiring the greatest differential pressure. The differential pressure setpoint shall not exceed 110 percent of that required to achieve design flow through the heat exchanger. Where differential pressure control is used to comply with this section, and DDC systems are used, the setpoint shall be reset downward based on valve positions until one valve is nearly wide open.

Exceptions:

(1) Differential pressure set-point reset is not required where valve position is used to comply with Section E 503.5.7.4.

(2) Variable-pump flow control is not required on heating-water pumps where more than 50 percent of annual heat is generated by an electric boiler.

(3) Variable flow is not required for primary pumps in a primary/secondary system.

(4) Variable flow is not required for a coil pump provided for freeze protection.

(5) Variable flow is not required for heat recovery coil runaround loops. [ASHRAE 90.1:6.5.4.2]

For SI units: 1 horsepower = 0.746 kW

E 503.5.7.3 Chiller and Boiler Isolation. Where a chilled-water plant includes more than one chiller, provisions shall be made so that the fluid flow through the chiller is automatically shut off where the chiller is shut down. Chillers piped in series for the purpose of increased temperature differential, shall be considered as one chiller. Where constant-speed chilled-water or condenser water pumps are used to serve multiple chillers, the number of pumps shall be not less than the number of chillers and staged on and off with the chillers. [ASHRAE 90.1:6.5.4.3.1]

E 503.5.7.3.1 Boiler Isolation. Where a boiler plant includes more than one boiler, provisions shall be made so that the flow through the boiler is automatically shut off where the boiler is shut down. Where constant-speed hot-water pumps are used to serve multiple boilers, the number of pumps shall be not less than the number of boilers and staged on and off with the boilers.

[ASHRAE 90.1:6.5.4.3.2]

E 503.5.7.4 Chilled- and Hot-Water Tempera- ture Reset Controls. Chilled- and hot-water systems with a design capacity exceeding 300 000 Btu/h (88 kW) supplying chilled or heated water to comfort conditioning systems shall include controls that automatically reset supply water temperatures by representative building loads (including return water temperature) or by outdoor air temperature. Where DDC is used to control valves, the set point shall be reset based on valve positions until one valve is nearly wide open or setpoint limits of the system equipment or application have been reached.

Exceptions:

(1) Where chilled-water supply is already cold, such as chilled water supplied from a district cooling or thermal energy storage system, such that blending would be required to achieve the reset chilled-water supply temperature.

(2) Where a specific temperature is required for a process application.

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APPENDIX E

(2) Piping systems that have equivalent or lower total pressure drop than the same system constructed with standard weight steel pipe with piping and fittings sized in accordance with Table E 503.5.7.6. [ASHRAE 90.1:6.5.4.6]

E 503.5.7.7 Chilled-Water Coil Selection.

Chilled-water cooling coils shall be selected to provide a 15°F (8°C) or higher temperature difference between leaving and entering water temperatures and a minimum of 57°F (14°C) leaving water temperature at design conditions.

Exceptions:

(1) Chilled-water cooling coils that have an air-side pressure drop exceeding 0.70 inch of water (0.17 kPa) when rated at 500 feet per minute (2.54 m/s) face velocity and dry conditions (no condensation).

(2) Individual fan-cooling units with a design supply airflow rate 5000 cubic feet per minute (ft [3] /min) (2.36 m [3] /s) and less.

(3) Constant-air-volume systems.

(4) Coils selected at the maximum temperature difference allowed by the chiller.

(5) Passive coils (no mechanically supplied airflow).

(6) Coils with design entering chilled-water temperatures of 50°F (10°C) and higher.

(7) Coils with design entering air dry-bulb temperatures of 65°F (18°C) and lower. [ASHRAE 90.1:6.5.4.7]

E 503.5.8 Heat Rejection Equipment. Section E 503.5.8 through Section E 503.5.9 applies to heat-rejection equipment used in comfort cooling systems, such as air-cooled condensers, dry coolers, open-circuit cooling towers, closed-circuit cooling towers, and evaporative condensers.

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(3) Water temperature reset is not required where valve position is used to comply with Section E 503.5.7. [ASHRAE 90.1:6.5.4.4]

E 503.5.7.5 Hydronic (Water Loop) Heat Pump and Water-Cooled Unitary Air Condi- tioners. Hydronic heat pumps and water-cooled unitary air-conditioners shall have a two-position automatic valve interlocked to shut off water flow

when the compressor is off.

Exception: Units employing fluid economizers.

[ASHRAE 90.1:6.5.4.5.1]

E 503.5.7.5.1 Controls. Hydronic heat pumps and water-cooled unitary air-conditioners having a total pump system power exceeding 5 hp (3.7 kW) shall have controls, devices, or both (such as variable speed control) that will result in pump motor demand of not more than 30 percent of design wattage at 50 percent of design water flow. [ASHRAE 90.1:6.5.4.5.2]

E 503.5.7.6 Pipe Sizing. Chilled-water and condenser-water piping shall be designed such that the design flow rate in each piping segment shall not exceed the values listed in Table E 503.5.7.6 for the

appropriate total annual hours of operation. Piping size selections for systems that operate under variable flow conditions (e.g., modulating two-way control valves at coils) and that contain variable-speed pump motors shall be permitted to be made from the “Variable Flow/Variable Speed” columns. All others shall be made from the “Other” columns.

Exceptions:

(1) Design flow rates exceeding the values in Table E 503.5.7.6 shall be permitted in specific sections of piping if the piping in question is not in the critical circuit at design conditions and is not predicted to be in the critical circuit during more than 30 percent of operating hours.

TABLE E 503.5.7.6 PIPING SYSTEM DESIGN MAXIMUM FLOW RATE (gallons per minute)

[ASHRAE 90.1: TABLE 6.5.4.6]

For SI units: 1 gallon per minute = 0.06 L/s, 1 foot per second = 0.3048 m/s, 1 inch = 25.4 mm

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APPENDIX E

Exception: Heat-rejection devices whose energy use is included in the equipment efficiency ratings listed in Table E 503.7.1(1) through Table E 503.7.1(4).

[ASHRAE 90.1:6.5.5.1]

E 503.5.8.1 Fan Speed Control. The fan system on a heat-rejection device powered by an individual motor or an array of motors with a connected power, including the motor service factor, totaling 5 hp (3.7 kW) or more shall have controls and/or devices (such as variable-speed control) that shall result in fan motor demand of no more than 30 percent of design wattage at 50 percent of the design airflow and that shall automatically modulate the fan speed to control the leaving fluid temperature or condensing temperature/pressure of the heat-rejection device.

Exceptions:

(1) Condenser fans serving multiple refrigerant or fluid cooling circuits.

(2) Condenser fans serving flooded condensers.

[ASHRAE 90.1:6.5.5.2.1]

E 503.5.8.2 Variable-Speed Fan Drives. Multicell heat rejection equipment with variable-speed fan drives shall:

(1) Operate the maximum number of fans allowed that comply with the manufacturer’s requirements for all system components.

(2) Control all fans to the same fan speed required for the instantaneous cooling duty, as opposed to staged (on/off) operation. Minimum fan speed shall comply with the minimum allowable speed of the fan drive system per the manufacturer’s recommendations. [ASHRAE 90.1:6.5.5.2.2]

E 503.5.9 Limitation on Centrifugal Fan Open- Circuit Cooling Towers. Centrifugal fan open-circuit cooling towers with a combined rated capacity of 1100 gallons per minute (gpm) (69.39 L/s) or greater at 95°F (35°C) condenser water return, 85°F (29°C) condenser water supply, and 75°F (24°C) outdoor air wet-bulb tem

perature shall comply with the energy efficiency requirement for axial fan open-circuit cooling towers in accordance with Table E 503.7.1(7).

Exception: Centrifugal open-circuit cooling towers that are ducted (inlet or discharge) or require external sound attenuation. [ASHRAE 90.1:6.5.5.3]

E 503.5.9.1 Tower Flow Turndown. Open-circuit cooling towers used on water-cooled chiller systems that are configured with multiple- or variable-speed condenser water pumps shall be designed so that all open-circuit cooling tower cells can be run in parallel with the larger of the following:

(1) The flow that is produced by the smallest pump at its minimum expected flow rate. (2) Fifty percent of the design flow for the cell.

[ASHRAE 90.1:6.5.5.4] E 503.5.10 Energy Recovery. Energy recovery shall be in accordance with Section E 503.5.10.1. through Section E 503.5.10.4.

E 503.5.10.1 Exhaust Air Energy Recovery. Exhaust air energy recovery shall be in accordance with Section E 503.5.10.1.1 through Section E 503.5.10.1.2(B). E 503.5.10.1.1 Exhaust Air Energy Recov- ery for Nontransient Dwelling Units. Nontransient dwelling units shall be provided with outdoor air energy recovery ventilation systems. For nontransient dwelling units, energy recovery systems shall result in an enthalpy recovery ratio of at least 50 percent at cooling design condition and at least 60 percent at heating design condition. The energy recovery system shall provide the required enthalpy recovery ratio at both heating and cooling design conditions, unless one mode is not required for the climate zone by the exceptions below. Exceptions: (1) Nontransient dwelling units in Climate Zone 3C.

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For SI units: 1 cubic foot per minute = 0.00047 m [3] /s

• NR = Not Required

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APPENDIX E

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For SI units: 1 cubic foot per minute = 0.00047 m [3] /s

• NR = Not Required

(3) Heating energy recovery where more than 60 percent of the outdoor air heating energy is provided from site-recovered energy or on-site renewable energy.

(4) Enthalpy recovery ratio requirements at heating design condition in Climate Zones 0, 1, and 2.

(5) Cooling energy recovery in climate zones 3C, 4C, 5B, 5C, 6B, 7, and 8.

(6) Where the sum of the airflow rates exhausted and relieved within 20 feet (6096 mm) of each other is less than 75 percent of the design outdoor airflow rate, excluding exhaust air that is;

(a) used for another energy recovery system,

(b) not allowed by ASHRAE/ASHE 170 for use in energy recovery systems with leakage potential, or

(c) of Class 4 as defined in Chapter 2 or ASHRAE 62.1.

(7) Heating energy recovery for systems in Climate Zones 0 through 4 requiring dehumidification during heating mode that employ energy recovery and have a minimum SERR of 0.40.

(8) Systems expected to operate less than 20 hours per week at the outdoor air percentage in accordance with Table E 503.5.10.1.2(1).

(9) Indoor pool dehumidifiers meeting Section E 503.5.10.4. [ASHRAE 90.1:6.5.6.1.2]

E 503.5.10.1.2(A) Minimum Enthalpy Recovery Ratio. Energy recovery systems required by this section shall result in an enthalpy recovery ratio of at least 50 percent. A 50 percent enthalpy recovery ratio shall mean a change in the enthalpy of the outdoor air supply equal to

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(2) Nontransient dwelling units with no more than 500 ft [2] (46.45 m [2] ) of conditioned floor area in Climate Zone 0, 1, 2, 3,4C, and 5C. (3) Enthalpy recovery ratio requirements at heating design condition in Climate Zones 0, 1, and 2. (4) Enthalpy recovery ratio requirements at cooling design condition in Climate Zones 4, 5, 6, 7, 8. [ASHRAE 90.1:6.5.6.1.1] E 503.5.10.1.2 Exhaust Air Energy Recov- ery for Spaces Other than Nontransient Dwelling Units. Each fan system serving spaces other than nontransient dwelling units shall have an energy recovery system where the design supply fan airflow rate exceeds the value listed in Table E 503.5.10.1.2(1) and Table E 503.5.10.1.2(2), based on the climate zone and percentage of outdoor air at design airflow conditions. Table E 503.5.10.1.2(1) shall be used for all ventilation systems that operate less than 8000 hours per year and Table E 503.5.10.1.2(2) shall be used for all ventilation systems that operate 8000 or more hours per year.

For spaces other than nontransient dwelling units, energy recovery systems required by this section shall result in an enthalpy recovery ratio of not less than 50 percent. The energy recovery system shall provide the required enthalpy recovery ratio both heating and cooling design conditions, unless one mode is not required for the climate zone by the exceptions below. Provision shall be provided to bypass or control the energy recovery system to permit air economizer operation in accordance with Section E 503.5.1.

Exceptions:

(1) Laboratory systems that are in accordance with Section E 503.5.11.3.

(2) Systems serving spaces that are not cooled and that are heated to less than 60°F (16°C).

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APPENDIX E

design exceeding 30 percent of the peak water-cooled condenser load at design conditions.

(2) Facilities that provide 60 percent of their service water heating from on-site-renewable energy or site-recovered energy or from other sources. [ASHRAE 90.1:6.5.6.2.2]

E 503.5.10.3 Heat Recovery for Space Con- ditioning. Where heating water is used for space heating, a condenser heat recovery system shall be installed, provided all of the following are true:

(1) The building is an acute inpatient hospital, where the building or portion of a building is used on a 24-hour basis for the inpatient medical, obstetric, or surgical care for patients.

(2) The total design chilled-water capacity for the acute inpatient hospital, either air cooled or water cooled, required at cooling design conditions exceeds 3 600 000 Btu/h (1055 kW) of cooling.

(3) Simultaneous heating and cooling occurs above 60°F (16°C) outdoor air temperature. The required heat recovery system shall have a cooling capacity that is at least 7 percent of the total design chilled-water capacity of the acute inpatient hospital at peak design conditions.

[ASHRAE 90.1:6.5.6.3]

E 503.5.10.4 Indoor Pool Dehumidifier Energy Recovery. An indoor pool dehumidifier serving a natatorium with a heated indoor pool over 500 ft [2] (46.45 m [2] ) in size shall include one of the following:

(1) An exhaust air sensible energy recovery system with a sensible energy recovery ratio of at least 50 percent.

(2) A condenser heat recovery system capable of and configured to use 100 percent of the heat generated through dehumidification to heat the pool water when there is a pool water heating load.

(3) An exhaust air energy recovery system that results in an enthalpy recovery ratio of at least 50 percent. [ASHRAE 90.1:6.5.6.4]

E 503.5.11 Exhaust Systems. Exhaust systems shall comply with Section E 503.5.11.1 through Section E 503.5.11.3.

E 503.5.11.1 Transfer Air. Conditioned supply air delivered to a space with a mechanical exhaust shall not exceed the greater of the following:

(1) The supply flow required to be in accordance with the space heating or cooling load;

(2) The ventilation rate required by the Authority Having Jurisdiction, the Facility Environmental Health and Safety department, Chapter 4 or ASHRAE 62.1; or

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50 percent of the difference between the outdoor air and entering exhaust air enthalpies at design conditions. The energy recovery system shall provide the required enthalpy recovery ratio at both heating and cooling design conditions unless one mode is not required for the climate zone by the exception in Section E 503.5.10.1.2(B). [ASHRAE 90.1: 6.5.6.1.2.1] E 503.5.10.1.2(B) Provision for Air Econo- mizer or Bypass Operation. Provision shall be made for both outdoor air and exhaust air to bypass or control the energy recovery system to enable economizer operation as required by Section E 503.5.1. The bypass or control shall meet the following criteria:

(1) For energy recovery systems where the transfer of energy cannot be stopped, bypass provision shall prevent the total airflow rate of either outdoor air or exhaust air through the energy recovery exchanger from exceeding 10 percent of the full design airflow rate.

(2) The pressure drop of the outdoor air through the energy recovery exchanger shall not exceed 0.4 in. of water (100 Pa); the pressure drop of the exhaust air through the energy recovery exchanger shall not exceed 0.4 in. of water (100 Pa).

Exception: Energy recovery systems with 80 percent or more outdoor air at full design airflow rate and not exceeding 10 000 CFM (4.72 m [3] /s).

[ASHRAE 90.1:6.5.6.1.2.2] E 503.5.10.2 Heat Recovery for Service Water Heating. Heat recovery shall comply with Section E 503.5.10.2.1 and Section E 503.5.10.2.2.

E 503.5.10.2.1 Condenser Heat Recovery Systems. Condenser heat recovery systems shall be installed for the heating or preheating of service hot water where all of the following conditions exist:

(1) The facility operates 24 hours a day.

(2) The total installed heat rejection capacity of the water-cooled system is more than 6 000 000 Btu/h (1757 kW) of heat rejection.

(3) The design service water heating load is more than 1 000 000 Btu/h (293 kW).

[ASHRAE 90.1:6.5.6.2.1] E 503.5.10.2.2 Capacity. The required heat recovery system shall have the capacity to provide the smaller of:

(1) Sixty percent of the peak heat-rejection load at design conditions or

(2) Preheat of the peak service hot-water draw to 85°F (29°C).

Exceptions:

(1) Facilities that employ condenser heat recovery for space heating with a heat recovery

444 2025 CALIFORNIA MECHANICAL CODE

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APPENDIX E

TABLE E 503.5.11.2.1 MAXIMUM NET EXHAUST FLOW RATE, CFM PER LINEAR FOOT OF HOOD LENGTH

[ASHRAE 90.1: TABLE 6.5.7.2.2]

For SI units: 1 foot = 304.8 mm, 1 cubic foot per minute = 0.00047 m [3] /s

(3) The mechanical exhaust flow minus the available transfer air from conditioned spaces or return air plenums on the same floor, not in different smoke or fire compartments, and that at their closest point are within 15 feet (4572 mm) of each other. Available transfer air is that portion of outdoor ventilation air that:

(a) is not required to satisfy other exhaust needs,

(b) is not required to maintain pressurization of other spaces, and

(c) is transferable according to applicable codes and standards and to the class of air recirculation limitations in Chapter 4 or ASHRAE 62.1.

Exceptions: (1) Biosafety level classified laboratories 3 or higher. (2) Vivarium spaces. (3) Spaces that are required by applicable codes and standards to be maintained at positive pressure relative to adjacent spaces. For spaces taking this exception, any transferable air that is not directly transferred shall be made available to the associated air-handling unit and shall be used whenever economizer or other options do not save more energy. (4) Spaces where the demand for transfer air may exceed the available transfer airflow rate and where the spaces have a required negative pressure relationship. For spaces taking this exception, any transferable air that is not directly transferred shall be made available to the associated air-handling unit and shall be used whenever economizer or other options do not save more energy. [ASHRAE 90.1:6.5.7.1] E 503.5.11.2 Kitchen Exhaust Systems. Replacement air introduced directly into the hood cavity of kitchen exhaust hoods shall not exceed 10 percent of the hood exhaust airflow rate. [ASHRAE 90.1:6.5.7.2.1]

E 503.5.11.2.1 Exhaust Flow Rate. Where a kitchen or dining facility has a total kitchen hood exhaust airflow rate exceeding 5000 ft [3] /min (2.3597 m [3] /s), each hood shall have an exhaust rate in accordance with Table E 503.5.11.2.1.

Where a single hood, or hood section, is installed over appliances with different duty ratings, the maximum allowable flow rate for the hood or

hood section shall not exceed the values in Table E 503.5.11.2.1 for the highest appliance duty rating under the hood or hood section. Refer to ASHRAE 154 for definitions of hood type, appliance duty, and net exhaust flow rate. Exception: Seventy-five percent or more of the total replacement air is transfer air that would otherwise be exhausted. [ASHRAE 90.1:6.5.7.2.2] E 503.5.11.2.2 Kitchen or Dining Facility. Where a kitchen or dining facility has a total kitchen hood exhaust airflow rate more than 5000 ft [3] /min (2.3597 m [3] /s), then one of the following shall be provided:

(1) Fifty percent or more of all replacement air is transfer air that would otherwise be

exhausted.

(2) Demand ventilation systems on 75 percent or more of the exhaust air. Such systems shall be capable of and configured to provide 50 percent or more reduction in exhaust and replacement air system airflow rates, including controls necessary to modulate airflow in response to appliance operation and to maintain full capture and containment of smoke, effluent, and combustion products during cooking and idle.

(3) Listed energy recovery devices that result in a sensible energy recovery ratio of 40 percent or more on 50 percent or more of the total exhaust airflow. A 40 percent sensible energy recovery ratio shall mean a change in the dry-bulb temperature of the outdoor air supply equal to 40 percent of the difference between the outdoor air and entering exhaust air dry-bulb temperatures at design conditions. [ASHRAE 90.1:6.5.7.2.3]

E 503.5.11.2.3 Performance Testing. An approved field test method shall be used to evaluate design air flow rates and demonstrate proper capture and containment performance of installed commercial kitchen exhaust systems. Where demand ventilation systems are utilized

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APPENDIX E

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E 503.5.12.2 Heating Enclosed Spaces. Radiant heating systems that are used as primary or supplemental heating for enclosed spaces shall be in conformance with the governing provisions of the standard, including, but not limited to the following:

(1) Radiant hydronic ceiling or floor panels (used for heating or cooling).

(2) Combination or hybrid systems incorporating radiant heating (or cooling) panels.

(3) Radiant heating (or cooling) panels used in conjunction with other systems such as VAV or thermal storage systems. [ASHRAE 90.1:6.5.8.2] E 503.5.13 Hot Gas Bypass Limitation. Cooling systems shall not use hot gas bypass or other evaporator pressure control systems unless the system is designed with multiple steps of unloading or continuous capacity modulation. The capacity of the hot gas bypass shall be limited as indicated in Table E 503.5.13 for VAV units and single-zone VAV units. Hot-gas bypass shall not be used on constant-volume units. [ASHRAE 90.1:6.5.9]

TABLE E 503.5.13

HOT GAS BYPASS LIMITATION

[ASHRAE 90.1: TABLE 6.5.9]

For SI units: 1000 British thermal units per hour = 0.293 kW

E 503.5.14 Door Switches. Conditioned spaces with doors, including doors with more than one-half glass, opening to the outdoors shall be provided with controls that when any such door is open, the following shall occur:

(1) Disable mechanical heating or reset the heating setpoint to 55°F (13°C) or lower within five minutes of the door opening.

(2) Disable mechanical cooling or reset the cooling setpoint to 90°F (32°C) or more within five minutes of the door opening. Mechanical cooling shall be permitted to remain enabled where outdoor air temperature is less than the space temperature.

Exceptions:

(1) Building entries with automatic closing devices.

(2) Any space without a thermostat.

(3) Alterations to existing buildings.

(4) Loading docks. [ASHRAE 90.1:6.5.10]

E 503.6 Submittals. The Authority Having Jurisdiction shall require submittal of compliance documentation and supplemental information in accordance with Section E 503.6.1 through Section E 503.6.3.

E 503.6.1 Construction Details. Compliance documents shall show all the pertinent data and features of the building, equipment, and systems in sufficient detail

TABLE E 503.5.13

HOT GAS BYPASS LIMITATION

[ASHRAE 90.1: TABLE 6.5.9]

For SI units: 1000 British thermal units per hour = 0.293 kW

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to be in accordance with Section E 503.5.11.2.2, additional performance testing shall be required to demonstrate proper capture and containment at minimum airflow. [ASHRAE 90.1:6.5.7.2.4]

E 503.5.11.3 Laboratory Exhaust Systems. Buildings with laboratory exhaust systems having a total exhaust rate of more than 5000 ft [3] /min (2.3597 m [3] /s) shall include not less than one of the following features:

(1) VAV laboratory exhaust and room supply systems capable of and configured to reduce exhaust and makeup airflow rates, incorporate a heat recovery system to precondition makeup air from laboratory exhaust, or both, and shall be in accordance with the following:

A + B - ( E/M ) ≥ 50% (Equation E 503.5.11.3)

Where:

A = Percentage that the exhaust and makeup airflow rates are capable of being reduced from design conditions.

B = Sensible energy recovery ratio.

E = Exhaust airflow rate through the heat recovery device at design conditions.

M = Makeup airflow rate of the system at design conditions.

(2) VAV laboratory exhaust and room supply systems that are required to have minimum circulation rates to be in accordance with the codes or

accreditation standards shall be capable of and configured to reduce zone exhaust and makeup airflow rates to the regulated minimum circulation values, or the minimum required to maintain pressurization relationship requirements. Systems serving nonregulated zones shall be capable of and configured to reduce exhaust and makeup airflow rates to 50 percent of the zone design values, or the minimum required to maintain pressurization relationship requirements.

reduce zone exhaust and makeup airflow rates to the regulated minimum circulation values, or the minimum required to maintain pressurization relationship requirements. Systems serving nonregulated zones shall be capable of and configured to reduce exhaust and makeup airflow rates to 50 percent of the zone design values, or the minimum required to maintain pressurization relationship requirements.

(3) Direct makeup (auxiliary) air supply of 75 percent or more of the exhaust airflow rate, heated not more than 2°F (1°C) below room setpoint, cooled to not less than 3°F (2°C) above room setpoint, no humidification added, and no simultaneous heating and cooling are used for dehumidification control. [ASHRAE 90.1:6.5.7.3]

E 503.5.12 Radiant Heating Systems. Radiant heating systems shall be in accordance with Section E 503.5.12.1 through Section E 503.5.12.2.

E 503.5.12.1 Heating Unenclosed Spaces. Radiant heating shall be used when heating is required for unenclosed spaces.

Exception: Loading docks equipped with air curtains. [ASHRAE 90.1:6.5.8.1]

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APPENDIX E

to permit a determination of compliance by the building official and to indicate compliance with the requirements of this appendix. [ASHRAE 90.1:4.2.2.1] E 503.6.2 Supplemental Information. Supplemental information necessary to verify compliance with this appendix, such as calculations, worksheets, compliance forms, vendor literature, or other data, shall be made available where required by the Authority Having Jurisdiction. [ASHRAE 90.1:4.2.2.2]

E 503.6.3 Manuals. Operating and maintenance information shall be provided to the building owner. This information shall include, but not be limited to, the information specified in Section E 503.6.3.1, Section E 503.6.3.2, and Section E 503.6.5.2. [ASHRAE 90.1:4.2.2.3]

E 503.6.3.1 Required Information. Construction documents shall require that an operating manual and maintenance manual be provided to the building owner. The manuals shall include, at a minimum, the following:

(1) Submittal data stating equipment rating and selected options for each piece of equipment requiring maintenance.

(2) Operation manuals and maintenance manuals for each piece of equipment requiring maintenance. Required routine maintenance actions shall be clearly identified.

(3) Names and addresses of not less than one qualified service agency.

(4) A complete narrative of how each system is intended to operate.

The Authority Having Jurisdiction shall only check to ensure that the construction documents require this information to be transmitted to the owner and should not expect copies of any of the materials.

[ASHRAE 90.1:8.7.3.2]

E 503.6.3.2 Lighting Manuals. Construction documents shall require for all lighting equipment and lighting controls that an operating manual and maintenance manual be provided to the building owner or the designated representative of the building owner within 90 days after the date of system acceptance. These manuals shall include, at a minimum, the following:

(1) Submittal data indicating all selected options for each piece of lighting equipment, including but not limited to lamps, ballasts, drivers, and lighting controls.

(2) Operation and maintenance manuals for each piece of lighting equipment and lighting controls with routine maintenance clearly identified including, as a minimum, a recommended relamping or cleaning program and a schedule for inspecting and recalibrating all lighting controls.

(3) A complete narrative of how each lighting control system is intended to operate including recommended settings. [ASHRAE 90.1:9.7.3.2]

E 503.6.4 Labeling of Material and Equipment. Materials and equipment shall be labeled in a manner that will allow for determination of their compliance with the applicable provisions of this appendix. [ASHRAE 90.1:4.2.3]

E 503.6.5 Completion Requirements. Section E 503.6.5.1 through Section E 503.6.5.4 are mandatory provisions and are necessary to comply with this appendix.

E 503.6.5.1 Drawings. Construction documents shall require that, within 90 days after the date of system acceptance, record documents be provided to the building owner or the designated representative of the building owner. Record documents shall include, as a minimum, the location and performance data on each piece of equipment, general configuration of the duct and pipe distribution system including sizes, and the terminal air or water design flow rates. [ASHRAE 90.1:6.7.3.1]

E 503.6.5.2 Manuals. Construction documents shall require that an operating manual and a maintenance manual be provided to the building owner or the designated representative of the building owner within 90 days after the date of system acceptance. These manuals shall be in accordance with industryaccepted standards and shall include, at a minimum, the following:

(1) Submittal data stating equipment size and selected options for each piece of equipment requiring maintenance.

(2) Operation manuals and maintenance manuals for each piece of equipment and system requiring maintenance, except equipment not furnished as part of the project. Required routine maintenance actions shall be clearly identified.

(3) Names and addresses of not less than one service agency.

(4) HVAC controls system maintenance and calibration information, including wiring diagrams, schematics, and control sequence descriptions. Desired or field-determined setpoints shall be permanently recorded on control drawings at control devices or, for digital control systems, in programming comments.

(5) A complete narrative of how each system is intended to operate, including suggested setpoints. [ASHRAE 90.1:6.7.3.2] E 503.6.5.3 System Balancing. Construction documents shall require that HVAC systems be balanced in accordance with generally accepted engineering standards. Construction documents shall require that a written balance report be provided to the building owner or the designated representative of the building owner for HVAC systems serving a total conditioned space or zone exceeding 5000 square feet (464.52 m [2] ). {ASHRAE 90.1:6.7.3.3.1}

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APPENDIX E

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E 503.6.5.3.1 Air System Balancing. Air systems shall be balanced in a manner to first minimize throttling losses. Then, for fans with fan system power greater than 1 hp (0.7 kW), fan speed shall be adjusted to meet design flow conditions. [ASHRAE 90.1:6.7.3.3.2]

E 503.6.5.3.2 Hydronic System Balanc- ing. Hydronic systems shall be proportionately balanced in a manner to first minimize throt tling losses; then the pump impeller shall be trimmed or pump speed shall be adjusted to meet design flow conditions.

Exceptions: Impellers need not be trimmed nor pump speed adjusted.

(1) For pumps with pump motors of 10 hp (7.5 kW) or less.

(2) Where throttling results is not greater than 5 percent of the nameplate horsepower draw, or 3 hp (2.2 kW), whichever is greater, above that required where the impeller was trimmed. [ASHRAE 90.1:6.7.3.3]

E 503.6.5.4 Minimum Level of Commission.

Commissioning shall be performed for HVAC systems in accordance with Level 1, Basic Commissioning of the SMACNA HVAC Systems Commissioning Manual. (See Section E 801.0 for additional information on HVAC system commissioning)

E 503.7 Minimum Equipment Efficiency Tables. The minimum efficiency requirements for equipment shall comply with Section E 503.7.1; duct insulation shall comply with Section E 503.7.2, and pipe insulation shall comply with Section E 503.7.3.

E 503.7.1 Minimum Efficiency Requirement Listed Equipment – Standard Rating and Oper- ating Conditions. The minimum efficiency requirements for equipment shall comply with Table E 503.7.1(1) through Table E 503.7.1(20).

E 503.7.2 Duct Insulation Tables. Duct insulation

shall comply with Table E 503.7.2.

E 503.7.3 Pipe Insulation Tables. Pipe insulation shall comply with Table E 503.7.3(1) and Table E 503.7.3(2).

E 503.8 Alternative Compliance Path, Computer Room Systems. HVAC systems only serving the heating, cooling, or ventilating needs of a computer room with IT equipment load greater than 13.4 hp (10 kW) shall be in accordance with ASHRAE 90.4. [ASHRAE 90.1:6.6.1]

E 504.0 Solar Energy Systems.

E 504.1 General. Solar energy systems shall be installed in accordance with the Uniform Solar, Hydronics and Geothermal Code (USHGC).

E 601.0 Indoor Environment.

E 601.1 Scope. The provisions of this section shall establish the means of reducing the quantity of air contaminants that are odorous, irritating, or harmful to the comfort and wellbeing of a building’s installers, occupants, and neighbors.

E 602.0 Fireplaces.

E 602.1 Requirements. A direct vent sealed-combustion gas or sealed wood-burning fireplace, or a sealed wood stove shall be installed. The fireplace shall comply with Section E 602.1.1 and Section E 602.1.2.

E 602.1.1 Masonry or Factory-Built Fireplace. Masonry and factory-built fireplaces located in conditioned spaces shall be in accordance with Section E 602.1.1.1 through Section E 602.1.1.3. E 602.1.1.1 Opening Cover. Closeable metal or glass doors covering the entire opening of the firebox shall be installed.

E 602.1.1.2 Combustion Air Intake. A combus tion air intake to draw air from the outside of the building directly into the firebox, which is an area of not less than 6 square inches (0.004 m [2] ) and is equipped with a readily accessible, operable, and tight-fitting damper or combustion air control device. E 602.1.1.3 Accessible Damper Control. The flue damper shall have a readily accessible control. Exception: Where a gas log, log lighter, or decorative gas appliance is installed in a fireplace, the flue damper shall be blocked open where required by this code or the manufacturer’s installation instructions.

E 602.1.2 Prohibited. Continuous burning pilot lights and the use of indoor air for cooling a firebox jacket, where the indoor air is vented to the outside of the building, are prohibited.

E 603.0 Pollutant Control.

E 603.1 Indoor Air Quality During Construction. Indoor air quality of a building shall be maintained in accordance with Section E 603.1.1 through Section E 603.1.3. E 603.1.1 Temporary Ventilation During Con- struction. Temporary ventilation during construction shall be provided in accordance with the following: (1) Ventilation during construction shall be achieved through openings in the building shell using fans to produce not less than three air changes per hour. (2) During dust-producing operations, the supply and return HVAC system openings shall be protected from dust in accordance with Section E 603.1.3.

(3) Where the building is occupied during demolition or construction, ventilation shall be provided in accordance with the Control Measures of the SMACNA IAQ Guidelines for Occupied Buildings Under Construction.

(4) The permanent HVAC system shall not be used during construction to condition and ventilate the build

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APPENDIX E

TABLE E 503.7.1(1) ELECTRICALLY OPERATED UNITARY AIR CONDITIONERS AND CONDENSING UNITS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-1]

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APPENDIX E

TABLE E 503.7.1(1) (continued) ELECTRICALLY OPERATED UNITARY AIR CONDITIONERS AND CONDENSING UNITS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-1]

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APPENDIX E

TABLE E 503.7.1(1) (continued) ELECTRICALLY OPERATED UNITARY AIR CONDITIONERS AND CONDENSING UNITS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-1]

For SI units: 1000 British thermal units per hour = 0.293 kW Notes: 1 ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 2 Single-phase, U.S. air-cooled air conditioners less than 65 000 Btu/h (19 kW) are regulated as consumer products by the U.S. Department of Energy Code of Federal Regulations 10 CFR 430. SEER and SEER2 values for single-phase products are set by the U.S. Department of Energy.

TABLE E 503.7.1(2) ELECTRICALLY OPERATED AIR-COOLED UNITARY

HEAT PUMPS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-2]

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APPENDIX E

TABLE E 503.7.1(2) (continued) ELECTRICALLY OPERATED AIR-COOLED UNITARY

HEAT PUMPS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-2]

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APPENDIX E

TABLE E 503.7.1(2) (continued) ELECTRICALLY OPERATED AIR-COOLED UNITARY

HEAT PUMPS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-2]

For SI units: 1000 British thermal units per hour = 0.293 kW, °C = (°F-32)/1.8

Notes: 1 ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 2 Single-phase, U.S. air-cooled heat pumps <65 000 Btu/h (19 kW) are regulated as consumer products by the U.S. Department of Energy Code of Federal Regulations 10 CFR 430. SEER, SEER2, and HSPF values for single-phase products are set by the U.S. Department of Energy.

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APPENDIX E

TABLE E 503.7.1(3) WATER-CHILLING PACKAGES ─ MINIMUM EFFICIENCY REQUIREMENTS [1, 2, 5]

[ASHRAE 90.1: TABLE 6.8.1-3]

For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per hour = 0.293 kW

Notes: 1 The requirements for centrifugal chillers shall be adjusted for nonstandard rating conditions per Section E 503.4.1 and are only applicable for the range of conditions listed there. The requirements for air-cooled, water-cooled positive displacement and absorption chillers are at standard rating conditions defined in the reference test procedure. 2 Both the full-load and IPLV.IP requirements must be met or exceeded to comply with this appendix. When there is a Path B, compliance can be with either Path A or Path B for any application. 3 ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 4 NA means the requirements are not applicable for Path B, and only Path A can be used for compliance. 5 FL is the full-load performance requirements, and IPLV.IP is for the part-load performance requirements.

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APPENDIX E

TABLE E 503.7.1(4) ELECTRICALLY OPERATED PACKAGED TERMINAL AIR CONDITIONERS, PACKAGED TERMINAL HEAT PUMPS, SINGLE-PACKAGE VERTICAL AIR CONDITIONERS, SINGLE-PACKAGE VERTICAL HEAT PUMPS, ROOM AIR CONDITIONERS, AND ROOM AIR CONDITIONER HEAT PUMPS ─ MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-4]

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APPENDIX E

TABLE E 503.7.1(4) (continued) ELECTRICALLY OPERATED PACKAGED TERMINAL AIR CONDITIONERS, PACKAGED TERMINAL HEAT PUMPS, SINGLE-PACKAGE VERTICAL AIR CONDITIONERS, SINGLE-PACKAGE VERTICAL HEAT PUMPS, ROOM AIR CONDITIONERS, AND ROOM AIR CONDITIONER HEAT PUMPS ─ MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-4]

For SI units: 1000 British thermal units per hour = 0.293 kW, °C = (°F-32)/1.8 Notes: 1 ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 2 Nonstandard size units must be factory labeled as follows: “MANUFACTURED FOR NONSTANDARD SIZE APPLICATIONS ONLY; NOT TO BE INSTALLED IN NEW STANDARD PROJECTS.” Nonstandard size efficiencies apply only to units being installed in existing sleeves having an external wall opening of less than 16 inch (406 mm) high or less than 42 inch (1067 mm) wide and having a cross-sectional area less than 670 square inches (0.432 m [2] ). 3 The cooling-mode wet-bulb temperature requirement only applies for units that reject condensate to the condenser coil. 4 Room air conditioners are regulated as consumer products by 10 CFR 430. For U.S. applications of room air conditioners, refer to Informative Appendix F, Table F-3, of ASHRAE 90.1 for the USDOE minimum efficiency requirements for U.S. applications. 5 “ Cap ” in EER and COPH equations for PTAC s and PTHP s means cooling capacity in Btu/h (kW) at 95°F (35°C) outdoor dry-bulb temperature.

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APPENDIX E

TABLE E 503.7.1(5) WARM-AIR FURNACES AND COMBINATION WARM-AIR FURNACES/AIR-CONDITIONING UNITS, WARM-AIR DUCT FURNACES, AND UNIT HEATERS ─ MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-5]

For SI units: 1000 British thermal units per hour = 0.293 kW

Notes: 1 ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 2 Combination units (i.e, furnaces contained within the same cabinet as an air conditioner) not covered by 10 CFR 430 [i.e., three-phase power or with cooling capacity greater than or equal to 65 000 Btu/h (19 kW)] may comply with either rating. All other units greater than 225 000 Btu/h (66 kW) sold in the U.S. must meet the AFUE standards for consumer products and test using USDOE’s AFUE test procedure at 10 CFR 430, Subpart B, Appendix N. 3 Compliance of multiple firing rate units shall be at the maximum firing rate. 4 Et = thermal efficiency. Units must also include an interrupted or intermittent ignition device (IID), have jacket losses not exceeding 0.75 percent of the input rating, and have either power venting or a flue damper. A vent damper is an acceptable alternative to a flue damper for those furnaces where combustion air is drawn from the conditioned space. 5 Ec = combustion efficiency (100 percent less flue losses). See test procedure for detailed discussion. 6 Units must also include an interrupted or intermittent ignition device (IID) and have either power venting or an automatic flue damper. 7 For U.S. applications of federal covered greater than 225 000 Btu/h (66 kW) products, see Informative Appendix F, Table F-4 of ASHRAE 90.1.

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APPENDIX E

TABLE E 503.7.1(6) GAS- AND OIL-FIRED BOILERS ─ MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-6]

For SI units: 1000 British thermal units per hour = 0.293 kW

Notes: 1 These requirements apply to boilers with rated input of 8 000 000 Btu/h (2343 kW) or less that are not packaged boilers and to all packaged boilers. Minimum efficiency requirements for boilers cover all capacities of packaged boilers. 2 Ec = combustion efficiency (100 percent less flue losses). See reference document for detailed information. 3 Et = thermal efficiency. See reference document for detailed information. 4 Maximum capacity—minimum and maximum ratings as provided for and allowed by the unit’s controls. 5 Includes oil-fired (residual). 6 Boilers shall not be equipped with a constant burning pilot light. 7 A boiler not equipped with a tankless domestic water-heating coil shall be equipped with an automatic means for adjusting the temperature of the water such that an incremental change in inferred heat load produces a corresponding incremental change in the temperature of the water supplied. 8 For new construction, refer to Section E 503.4 for additional system compliance requirements. 9 See Informative Appendix F, Table F-4 of ASHRAE 90.1, for U.S. minimum efficiencies for residential products covered by USDOE requirements for U.S. applications.

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APPENDIX E

TABLE E 503.7.1(7) PERFORMANCE REQUIREMENTS FOR HEAT REJECTION EQUIPMENT—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-7]

For SI units: °C = (°F-32)/1.8, 1 gallon per minute per horsepower = 0.085 [(L/s)/kW], 1000 British thermal units per hour = 0.293 kW, 1 horsepower = 0.746 kW

Notes: 1 For purposes of this table, open-circuit cooling tower performance is defined as the water flow rating of the tower at the thermal rating condition listed in Table E 503.7.1(7) divided by the fan motor nameplate power. 2 For purposes of this table, closed-circuit cooling tower performance is defined as the process water flow rating of the tower at the thermal rating condition listed in Table E 503.7.1(7) divided by the sum of the fan motor nameplate power and the integral spray pump motor nameplate power. 3 For purposes of this table, dry-cooler performance is defined as the process water flow rating of the unit at the thermal rating condition listed in this table divided by the total fan motor nameplate power of the unit, and air-cooled condenser performance is defined as the heat rejected from the refrigerant divided by the total fan motor nameplate power of the unit. 4 ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 5 The efficiencies and test procedures for both open- and closed-circuit cooling towers are not applicable to hybrid cooling towers that contain a combination of separate wet and dry heat exchange sections. The certification requirements do not apply to field-erected cooling towers. 6 All cooling towers shall comply with the minimum efficiency listed in the table for that specific type of tower with the capacity effect of any project-specific accessories and/or options included in the capacity of the cooling tower. 7 For purposes of this table, evaporative condenser performance is defined as the heat rejected at the specified rating condition in the table, divided by the sum of the fan motor nameplate power and the integral spray pump nameplate power. 8 Requirements for evaporative condensers are listed with ammonia (R-717) and R-448A as test fluids in the table. Evaporative condensers intended for use with halocarbon refrigerants other than R-448A must meet the minimum efficiency requirements listed above with R-448A as the test fluid. For ammonia, the condensing temperature is defined as the saturation temperature corresponding to the refrigerant pressure at the condenser entrance. For R-448A, which is a zeotropic refrigerant, the condensing temperature is defined as the arithmetic average of the dew point and the bubble point temperatures corresponding to the refrigerant pressure at the condenser entrance.

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APPENDIX E

TABLE E 503.7.1(8) ELECTRICALLY OPERATED VARIABLE-REFRIGERANT-FLOW AIR CONDITIONERS ─ MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-8]

For SI units: 1000 British thermal units per hour = 0.293 kW

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APPENDIX E

TABLE E 503.7.1(9) « ELECTRICALLY OPERATED VARIABLE-REFRIGERANT-FLOW AND APPLIED

HEAT PUMPS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-9]

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APPENDIX E

TABLE E 503.7.1(9) (continued) ELECTRICALLY OPERATED VARIABLE-REFRIGERANT-FLOW AND APPLIED

HEAT PUMPS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-9]

For SI units: 1000 British thermal units per hour = 0.293 kW, °C=(°F-32)/1.8

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APPENDIX E

TABLE E 503.7.1(10) FLOOR-MOUNTED AIR CONDITIONERS AND CONDENSING UNITS

SERVING COMPUTER ROOMS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-10]

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APPENDIX E

TABLE E 503.7.1(10) (continued) FLOOR-MOUNTED AIR CONDITIONERS AND CONDENSING UNITS

SERVING COMPUTER ROOMS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-10]

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APPENDIX E

TABLE E 503.7.1(10) (continued) FLOOR-MOUNTED AIR CONDITIONERS AND CONDENSING UNITS

SERVING COMPUTER ROOMS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-10]

For SI units: 1000 British thermal units per hour = 0.293 kW, °C=(°F-32)/1.8

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APPENDIX E

TABLE E 503.7.1(11) COMMERCIAL REFRIGERATORS, COMMERCIAL FREEZERS, AND REFRIGERATION—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-11]

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APPENDIX E

TABLE E 503.7.1(11) (continued) COMMERCIAL REFRIGERATORS, COMMERCIAL FREEZERS, AND REFRIGERATION—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-11]

For SI units: °C=(°F-32)/1.8

Notes:

1 The meaning of the letters in this column is indicated in the columns to the left. 2 “Ice-cream freezer” is defined in 10 CFR 431.62 as a commercial freezer that is designed to operate at or below –5°F and that the manufacturer designs, markets, or intends for the storing, displaying, or dispensing of ice cream. 3 Equipment class designations consist of a combination (in sequential order separated by periods (AAA).(BB).(C)) of the following: a. (AAA)—An equipment family code (VOP = vertical open, SVO = semivertical open, HZO = horizontal open, VCT = vertical closed transparent doors, VCS = vertical closed solid doors, HCT = horizontal closed transparent doors, HCS = horizontal closed solid doors, and SOC = service over counter); b. (BB)—An operating mode code (RC = remote condensing and SC = self-contained); and c. (C)—A rating temperature code [M = medium temperature (38°F), L = low temperature (0°F), or I = ice cream temperature (–15°F)]. For example, “VOP.RC.M” refers to the “vertical open, remote condensing, medium temperature” equipment class. 4 V is the volume of the case (ft 3 ) as measured in AHRI 1200, Appendix C. 5 TDA is the total display area of the case (ft 2 ) as measured in AHRI 1200, Appendix D.

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APPENDIX E

TABLE E 503.7.1(12) VAPOR COMPRESSION BASED INDOOR POOL DEHUMIDIFIERS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-12]

TABLE E 503.7.1(14) ELECTRICALLY OPERATED DX-DOAS UNITS, SINGLE-PACKAGE AND REMOTE CONDENSER, WITH ENERGY RECOVERY—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-14]

TABLE E 503.7.1(13) ELECTRICALLY OPERATED DX-DOAS UNITS, SINGLE-PACKAGE AND REMOTE CONDENSER, WITHOUT ENERGY RECOVERY—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-13]

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APPENDIX E

TABLE E 503.7.1(15) ELECTRICALLY OPERATED WATER-SOURCE HEAT PUMPS—MINIMUM EFFICIENCY REQUIREMENTS [2]

[ASHRAE 90.1: TABLE 6.8.1-15]

For SI units: 1000 British thermal units per hour = 0.293 kW, °C = (°F-32)/1.8

Notes: 1 Section 12 of ASHRAE 90.1 contains a complete specification of the referenced test procedure, including the referenced year version of the test procedure. 2 Single-phase, U.S. air-cooled heat pumps less than 65 000 Btu/h (19 kW) are regulated as consumer products by 10 CFR 430. SCOPC, SCOP2C, SCOPH and SCOP2H values for single-phase products are set by the USDOE. See Informative Appendix F of ASHRAE 90.1 for the USDOE minimum.

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APPENDIX E

TABLE E 503.7.1(16) HEAT-PUMP AND HEAT RECOVERY CHILLER PACKAGES—MINIMUM EFFICIENCY REQUIREMENTS

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APPENDIX E

TABLE E 503.7.1(16) (continued) HEAT-PUMP AND HEAT RECOVERY CHILLER PACKAGES—MINIMUM EFFICIENCY REQUIREMENTS

For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per hour = 0.293 kW, °C=(°F-32)/1.8

Notes:

1 Cooling-only rating conditions are standard rating conditions defined in AHRI 550/590, Table 1. 2 Heating full-load rating conditions are at rating conditions defined in AHRI 550/590, Table 1. 3 For water-cooled heat recovery chillers that have capabilities for heat rejection to a heat recovery condenser and a tower condenser, the COPHR applies to operation at full load with 100 percent heat recovery (no tower rejection). Units that only have capabilities for partial heat recovery shall meet the requirements of Table E 503.7.1(3). 4 Outdoor air entering dry-bulb (db) temperature and wet-bulb (wb) temperature. 5 Source-water entering and leaving water temperature.

TABLE E 503.7.1(17) CEILING-MOUNTED COMPUTER-ROOM AIR CONDITIONERS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-17]

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APPENDIX E

TABLE E 503.7.1(17) (continued) CEILING-MOUNTED COMPUTER-ROOM AIR CONDITIONERS—MINIMUM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-17]

For SI units: 1000 British thermal units per hour = 0.293 kW, °C=(°F-32)/1.8

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APPENDIX E

TABLE E 503.7.1(18) WALK-IN COOLER AND FREEZER DISPLAY DOOR EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-18]

  - _Add_ is the surface area (ft [2] ) of the display door.

TABLE E 503.7.1(19) WALK-IN COOLER AND FREEZER NONDISPLAY DOOR EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-19]

  - _And_ is the surface area (ft [2] ) of the non-display door.

TABLE E 503.7.1(20) WALK-IN COOLER AND FREEZER REFRIGERATION SYSTEM EFFICIENCY REQUIREMENTS

[ASHRAE 90.1: TABLE 6.8.1-20]

For SI units: 1000 British thermal units per hour = 0.293 kW

• qnet is net capacity (Btu/h) as determined in accordance with AHRI 1250.

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APPENDIX E

Notes: 1 Insulation R-values, measured in [°F•h•ft 2 /(Btu•in)] [(m•K)/W], are for the insulation as installed and do not include film resistance. The required minimum thicknesses do not consider water vapor transmission and possible surface condensation. Where portions of the building envelope are used as a plenum enclosure, building envelope insulation shall be as required by the most restrictive condition of Section E 503.4.7.1 or ASHRAE 90.1, depending on whether the plenum is located in the roof, wall, or floor. Insulation resistance measured on a horizontal plane in accordance with ASTM C518 at a mean temperature of 75°F (24°C) at the installed thickness. 2 Includes attics above insulated ceilings, parking garages and crawl spaces. 3 Includes return air plenums, with or without exposed roofs above. 4 Return ducts in this duct location do not require insulation.

TABLE E 503.7.3(1) MINIMUM PIPE INSULATION THICKNESS FOR HEATING AND HOT WATER SYSTEMS [1, 2, 3, 4, 5]

(STEAM, STEAM CONDENSATE, HOT WATER HEATING, AND DOMESTIC WATER SYSTEMS)

[ASHRAE 90.1: TABLE 6.8.3-1]

For SI units: °C=(°F-32)/1.8, 1 inch = 25 mm, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/(m•K)]

Notes: 1 For insulation outside the stated conductivity range, the minimum thickness ( T ) shall be determined as follows: T = r {(1 + t / r ) [K] [/] [k ] – 1}

Where:

T = minimum insulation thickness (inches). r = actual outside radius of pipe (inches). t = insulation thickness listed in this table for applicable fluid temperature and pipe size. K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu•in/(h•ft [2] - °F)] [W/(m•K)]. k = the upper value of the conductivity range listed in this table for the applicable fluid temperature. 2 These thicknesses are on energy efficiency considerations only. Additional insulation is sometimes required relative to safety issues/surface temperature. 3 For piping smaller than 1 1 ⁄ 2 inches (40 mm) or less and located in partitions within conditioned spaces, reduction of these thicknesses by 1 inch (25.4 mm) shall be permitted (before thickness adjustment required in footnote 1) but not to thicknesses below 1 inch (25.4 mm). 4 For direct-buried heating and hot water system piping, reduction of these thicknesses by 1 1 ⁄ 2 inch (40 mm) shall be permitted (before thickness adjustment required in footnote 1) but not to thicknesses below 1 inch (25.4 mm). 5 Table E 503.7.3(1) is based on steel pipe. Nonmetallic pipes schedule 80 thickness or less shall use the table values. For other nonmetallic pipes having thermal resistance more than that of steel pipe, reduced insulation thicknesses are permitted where documentation is provided showing that the pipe with the proposed insulation has no more heat transfer per foot (mm) than a steel pipe of the same size with the insulation thickness shown in Table E 503.7.3(1).

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APPENDIX E

TABLE E 503.7.3(2) MINIMUM PIPE INSULATION THICKNESS FOR COOLING SYSTEMS (CHILLED WATER, BRINE, AND REFRIGERANT) [1,2,3,4 ]

[ASHRAE 90.1: TABLE 6.8.3-2]

For SI units: °C = (°F-32)/1.8, 1 inch = 25 mm, 1 British thermal unit inch per hour square foot degree Fahrenheit = [0.1 W/(m•k)]

Notes: 1 For insulation outside the stated conductivity range, the minimum thickness ( T ) shall be determined as follows: T = r {(1 + t/r ) [K/k ] – 1}

Where:

T = minimum insulation thickness (inches). r = actual outside radius of pipe (inches). t = insulation thickness listed in this table for applicable fluid temperature and pipe size. K = conductivity of alternate material at mean rating temperature indicated for the applicable fluid temperature [Btu • inch/(h • ft [2] • °F)] [W/(m•K)]. k = the upper value of the conductivity range listed in this table for the applicable fluid temperature. 2 These thicknesses are based on energy efficiency considerations only. Issues such as water, vapor permeability, or surface condensation require vapor retarders or additional insulation. 3 For direct-buried cooling system piping, insulation is not required. 4 Table E 503.7.3(2) is based on steel pipe. Nonmetallic pipes schedule 80 thickness or less shall use the table values. For other nonmetallic pipes having thermal resistance more than that of steel pipe, reduced insulation thicknesses are permitted where documentation is provided showing that the pipe with the proposed insulation has no more heat transfer per foot (mm) than a steel pipe of the same size with the insulation thickness shown in Table E 503.7.3(2).

ing within the required temperature range for material and equipment installation. Where required, a supplemental HVAC system shall be used during construction, return air shall be equipped with filters with a minimum efficiency reporting value (MERV) of 8, in accordance with ASHRAE 52.2, or an average efficiency of 30 percent in accordance with ASHRAE 52.2. Before occupancy, filters shall be replaced with filters having a MERV 13 rating in accordance with Section E 603.3.

Exception: Embedded hydronics system shall be permitted to be used to condition the building during construction.

E 603.1.2 Indoor Air Quality After Construction. After construction ends and interior finishes are installed, flush-out the building to reduce contaminant concentrations by supplying a total outdoor air volume of 14 000 cubic feet per square foot (ft [3] /ft [2] ) (4267.2 m [3] /m [2] ) of occupiable building area. An internal temperature of not less than 60°F (16°C) and relative humidity not higher than 60 percent shall be maintained during the flush-out process. Occupancy shall begin on condition of 3500 ft [3] /ft [2] (1066.8 m [3] /m [2] ) of building area, with the remaining 10 500 ft [3] /ft [2] (3200.4 m [3] /m [2] ) being accomplished as soon as possible.

Exception: Other means of reducing the contaminant concentration levels shall be permitted where approved by the Authority Having Jurisdiction. E 603.1.3 Covering of Duct Openings and Pro- tection of Mechanical Equipment During Con- struction. At the time of rough installation, or during storage on the construction site and until final startup of the heating and cooling equipment, duct and other related air distribution component openings shall be covered

shall be permitted where approved by the Authority Having Jurisdiction. E 603.1.3 Covering of Duct Openings and Pro- tection of Mechanical Equipment During Con- struction. At the time of rough installation, or during storage on the construction site and until final startup of the heating and cooling equipment, duct and other related air distribution component openings shall be covered

with tape, plastic, sheet metal, or other methods acceptable to the Authority Having Jurisdiction to reduce the amount of dust or debris that collects in the system.

E 603.2 Isolation of Pollutant Sources. Rooms where activities produce hazardous fumes or chemicals, including commercial kitchens, garages, janitorial or laundry rooms, and copy or printing rooms, shall be exhausted and isolated from adjacent spaces in accordance with this code.

E 603.3 Filters. In mechanically ventilated buildings, particle filters, or air-cleaning devices shall be provided to clean outdoor and return air prior to its delivery to occupied spaces. The particle or air cleaner shall have a MERV of 13.

Exception: A filter or air cleaning device with a lower MERV value shall be permitted provided it is the highest value commercially available for the specific equipment that is installed.

E 603.4 Ozone Depletion and Global Warming Reductions. Installations of HVAC and refrigeration shall not contain CFCs and shall be in accordance with this code.

E 604.0 Indoor Moisture Control.

E 604.1 Rainwater Control. Roof drainage systems shall discharge to a place of disposal in accordance with the plumbing code. Storm water shall be directed away from the building.

E 605.0 Indoor Air Quality for Low-Rise Residential. E 605.1 General. Rooms or occupied spaces within singlefamily homes and multifamily structures of three stories or less above grade shall be designed to have ventilation (outdoor) air for occupants in accordance with Section E 605.1.1 through Section E 605.1.3.2, or the applicable local code.

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APPENDIX E

E 605.1.1 Natural Ventilation. Naturally ventilated spaces shall be permanently open to and within 20 feet (6096 mm) of operable wall or roof openings to the outdoors, the openable area of which is not less than 5 percent of the conditioned floor area of the naturally ventilated space. Where openings are covered with louvers or otherwise obstructed, openable area shall be based on the free unobstructed area through the opening. E 605.1.1.1 Access to Operable Openings. The means to open required operable openings shall be readily accessible to building occupants where the space is occupied.

E 605.1.2 Mechanical Ventilation. Each space that is not naturally ventilated in accordance with Section E 605.1.1 shall be ventilated with a mechanical system capable of providing an outdoor air rate not less than 15 ft [3] /min (0.007 m [3] /s) per person times the expected number of occupants. Mechanical ventilation shall comply with this code.

E 605.1.3 Dwelling Unit Ventilation. A mechanical exhaust system, supply system, or combination thereof shall be designed and provided with the capacity to deliver outdoor air ventilation to the whole dwelling unit at a continuous rate not less than that specified in Section E 605.1.3.1 through Section E 605.1.3.5. [ASHRAE 62.2:4.1]

E 605.1.3.1 Total Ventilation Rate. The total required ventilation rate ( Qtot ) shall be as specified in Table E 605.1.3.1 or, alternatively, calculated using Equation E 605.1.3.1.

(Equation E 605.1.3.1) Qtot = 0.03 Afloor + 7.5( Nbr + 1)

Where:

Qtot = total required ventilation rate, CFM Afloor = dwelling unit floor area, ft [2] Nbr = number of bedrooms (not to be less than one)

For SI units: 1 cubic foot per minute = 0.00047 m [3] /s, 1 cubic foot

per minute = 0.4719 L/s

Exceptions: Dwelling-unit mechanical ventilation systems shall not be required where the Authority Having Jurisdiction determines that window operation is a locally permissible method of providing ventilation and provided one or more of the following conditions is met:

(1) The building has no mechanical cooling and is in zone 1 or 2 of the climate zone map.

(2) The building is thermally conditioned for human occupancy for less than 876 hours per year. [ASHRAE 62.2:4.1.1] E 605.1.3.2 Effective Annual Average Infiltra- tion Rate ( Qinf ) Using a Single-Point Enve- lope Leakage Test. Effective Annual Average

Infiltration Rate ( Qinf ) shall be calculated using a single-point test at 0.007 psi (50 Pa). The Effective Annual Average Infiltration Rate ( Qinf ) shall be calculated using Equation 605.1.3.2:

(Equation E 605.1.3.2) Qinf = 0.052 × Q 50 × wsf × ( H/Hr ) [z]

Where: Qinf = estimated infiltration rate, CFM (L/s). Q50 = leakage rate at 0.007 psi (50 Pa) depressurization or pressurization, CFM (L/s). wsf = weather and shielding factor from ASHRAE 62.2.

H = vertical distance between the lowest and highest above-grade points within the pressure boundary, ft (m). Hr = reference height, 8.2 ft (2.5 m). z = 0.4 for the purpose of calculating the Effective Annual Average Infiltration Rate.

For SI units: 1 foot = 0.3048 m, 1 cubic foot per minute =

0.4719 L/s

{ASHRAE 62.2:4.1.2.1} E 605.1.3.3 Required Mechanical Ventilation Rate ( Qfan ). If a blower door test has been performed, then a credit for estimated infiltration may be taken for detached dwelling units using either the procedure in Section E 605.1.3.2 or E 605.1.3.4. Attached dwelling units other than horizontally attached shall not be permitted to take an infiltration credit. Horizontally attached dwelling units shall be permitted to use a blower door test result to take this credit, subject to the reduction factor Aext in Equation E 605.1.3.3.

If this credit is taken, then the Required Mechanical Ventilation Rate ( Qfan ) shall be calculated using Equation E 605.1.3.3: (Equation E 605.1.3.3) Qfan = Qtot – Φ ( Qinf × Aext )

Where: Qfan = required mechanical ventilation rate, CFM (L/s) Qtot = total required ventilation rate, CFM (L/s) Qinf = infiltration, CFM (L/s) (see ASHRAE 62.2 for exceptions for existing buildings) Aext = 1 for detached dwelling units; otherwise, for horizontally attached dwelling units, the ratio of exterior envelope surface area that is not attached to garages or other dwelling units to total envelope surface area. Φ = 1 for balanced ventilation systems, and Qinf / Qtot otherwise.

For SI units: 1 cubic foot per minute = 0.4719 L/s

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APPENDIX E

For SI units: 1 square foot = 0.0929 m [2], 1 cubic foot per minute = 0.00047 m [3] /s

Exception: Where Qfan, calculated for unbalanced ventilation, is less than or equal to 15 CFM (7 L/s), a dwelling-unit ventilation system is not required.

[ASHRAE 62.2:4.1.2] E 605.1.3.4 Effective Annual Average Infiltra- tion Rate ( Qinf ) Using a Multipoint Envelope Leakage Test. Effective Annual Average Infiltration Rate ( Qinf ) shall be calculated using the normalized leakage calculated from measurements of envelope leakage using a multipoint test from either ASTM E779 in accordance with Section E 605.1.3.4(A) or CGSB 149.10 in accordance with Section E 605.1.3.4(B). E 605.1.3.4(A) ASTM Procedure. To calculate the effective leak area ( ELA ) from ASTM E779, the leakage area for pressurization and depressurization (using a 0.0006 psi [4 Pa] reference pressure) shall be averaged using Equation E 605.1.3.4(A):

[Equation E 605.1.3.4(A)]

ELA = ( Lpress + Ldepress )/ 2

Where:

ELA = effective leakage area, ft [2] (m [2] ) Lpress = leakage area from pressurization, ft [2 ] (m [2] ) Ldepress = leakage area from depressurization, ft [2 ] (m [2] )

For SI units: 1 square foot = 0.0929 m [2]

E 605.1.3.4(B) CGSB Procedure. To calculate the ELA from CGSB 149.10, the following modifications to the test procedure must be made:

(1) All vents and intentional openings must be in the same configuration as specified in ASTM E779 (i.e., HVAC dampers and registers should be in the normal operating position; fireplace and

other dampers should be closed unless they are required for test operation). (2) Height and floor area must be reported consistently with the definitions of this standard. (3) The leakage area as calculated from the CGSB procedure must be converted using Equation E 605.1.3.4(B):

[Equation E 605.1.3.4(B)] ELA = 0.61 × (0.4) [n] – 0.5 × Lcgsb

Where:

n = exponent measured from the CGSB 149.10 Lcgsb = CGSB leakage area as modified above, ft [2 ] (m [2] )

For SI units: 1 square foot = 0.0929 m [2] E 605.1.3.4(C) Normalized Leakage. Normalized leakage shall be calculated using Equation E 605.1.3.4(C):

[Equation E 605.1.3.4(C)]

ELA H z NL = 1000 x x

Afloor [ Hr ]

Where:

NL = normalized leakage ELA = effective leakage area, ft [2] (m [2] ) Afloor = floor area of residence, ft [2] (m [2] ) H = vertical distance between the lowest and highest above-grade points within the pressure boundary, ft (m) Hr = reference height, 8.2 ft (2.5 m) z = 0.4 for the purpose of calculating the Effective Annual Infiltration Rate

For SI units: 1 foot = 0.3048 m, 1 square foot = 0.0929 m [2]

ELA H z NL = 1000 x x [ Hr ]

Afloor Hr

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APPENDIX E

Exception: For multifamily dwelling units, the manual ON-OFF control shall not be required to be readily accessible. [ASHRAE 62.2:4.4, 4.4.1] E 605.1.6.1 Operation. The system shall be operated as designed. [ASHRAE 62.2:4.4.2] E 605.1.7 Variable Mechanical Ventilation. Dwellingunit mechanical ventilation systems designed to provide variable ventilation shall comply with Section E 605.1.7.1, Section E 605.1.7.2, or Section E 605.1.7.3. Section E 605.1.7.2 and Section E 605.1.7.3 also require compliance with ASHRAE 62.2 and require verification with supporting documentation from the manufacturer, designer, or specifier of the ventilation control system that the system meets the requirements of these sections. Tracking or scheduling of occupancy shall be permitted. [ASHRAE 62.2:4.5] E 605.1.7.1 Short-Term Average Ventilation. To comply with this section, a variable ventilation system shall be installed to provide an average dwellingunit ventilation rate over each consecutive period of three hours or less that is greater than or equal to Qfan as calculated using Section E 605.1.3.3, and shall not provide a ventilation rate of zero over any three-hour interval. [ASHRAE 62.2:4.5.1]

.7.1 Short-Term Average Ventilation.** To comply with this section, a variable ventilation system shall be installed to provide an average dwellingunit ventilation rate over each consecutive period of three hours or less that is greater than or equal to Qfan as calculated using Section E 605.1.3.3, and shall not provide a ventilation rate of zero over any three-hour interval. [ASHRAE 62.2:4.5.1]

E 605.1.7.2 Scheduled Ventilation. This section shall only be used when one or more fixed patterns of designed ventilation are known at the time compliance to Section E 605.0 is being determined. Such patterns include those both clock-driven and driven by typical meteorological data. Compliance with this section shall be demonstrated with either Section E 605.1.7.2.1 or Section E 605.1.7.2.2. [ASHRAE 62.2:4.5.2] E 605.1.7.2.1 Annual Average Schedule. An annual schedule of ventilation complies with this section when the annual average relative exposure is no more than one, and the peak relative exposure shall not exceed five for any time step as calculated in accordance with ASHRAE 62.2. [ASHRAE 62.2:4.5.2.1] E 605.1.7.2.2 Block Scheduling. The schedule of ventilation complies with this section if it is broken into blocks of time and each block individually has an average relative exposure during occupied periods that is no more than one as calculated in ASHRAE 62.2. All blocks shall end with a relative exposure less than or equal to one. [ASHRAE 62.2:4.5.2.2]

E 605.1.7.3 Real-Time Control. A real-time ventilation controller complies with this section when it is designed to adjust the ventilation system based on real-time input to the ventilation calculations so that the average relative exposure during occupied periods is no more than one, and the peak relative exposure shall not exceed five for any time step as calculated in ASHRAE 62.2. The averaging period shall be no more than one year and shall be based on simple, recursive or running average, but not extrapolation.

»

E 605.1.3.4(D) Effective Annual Average Infil- tration Rate. Effective Annual Average Infiltration Rate ( Qinf ) shall be calculated using Equation E 605.1.3.4(D):

[Equation E 605.1.3.4(D)]

= [NL] [ • ] [wsf] [ • ] [A][f][loor] Qinf (CFM) 7.3

Where:

NL = normalized leakage wsf = weather and shielding factor from ASHRAE 62.2 Afloor = floor area of residence, ft [2 ]

For SI units: 1 cubic foot per minute = 0.4719 L/s

[ASHRAE 62.2:4.1.2.2] E 605.1.3.5 Different Occupant Density. Table E 605.1.3.1 and Equation E 605.1.3.1 assume two persons in a studio or one-bedroom dwelling unit and an additional person for each additional bedroom. Where higher occupant densities are known, the rate shall be increased by 7.5 ft [3] /min (0.003 m [3] /s) for each additional person. Where approved by the Authority Having Jurisdiction, lower occupant densities shall be permitted to be used. [ASHRAE 62.2:4.1.3] E 605.1.4 System Type. The dwelling-unit mechanical ventilation system shall consist of one or more supply or exhaust fans and associated ducts and controls. Local exhaust fans shall be permitted to be part of a mechanical exhaust system. Where local exhaust fans are used to provide dwelling-unit ventilation, the local exhaust airflow shall be permitted to be credited toward the dwelling-unit ventilation airflow requirement. Outdoor air ducts connected to the return side of an air handler shall be permitted as supply ventilation where manufacturer’s requirements for return air temperature are met. See ASHRAE Indoor Air Quality Guide for guidance on selection of methods. [ASHRAE 62.2:4.2] E 605.1.5 Airflow Measurement. The airflow required by this section shall be the quantity of outdoor ventilation air supplied and/or indoor air exhausted by the mechanical ventilation system as installed and shall be measured according to the ventilation equipment manufacturer’s installation instructions, or by using a flow hood, flow grid, or other airflow measuring device at the mechanical ventilation fan’s inlet terminals/grilles, outlet terminals/grilles, or in the connected ventilation ducts. Balanced mechanical ventilation system airflow shall be the average of the supply fan and exhaust fan flows. Ventilation airflow of systems with multiple operating modes shall be tested in all modes designed to meet this section.

[ASHRAE 62.2:4.3] E 605.1.6 Control and Operation. A readily accessible manual ON-OFF control, including but not limited to a fan switch or a dedicated branch-circuit overcurrent device, shall be provided. Controls shall include text or an icon indicating the system’s function.

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APPENDIX E

For the purposes of calculating average relative exposure, a dwelling unit shall be permitted to be treated as unoccupied during a time step only if it is unoccupied for the entire time step. [ASHRAE 62.2:4.5.3] E 605.1.8 Equivalent Ventilation. A dwelling-unit ventilation system shall be designed and operated in such a way as to provide the same or lower annual exposure as would be provided in accordance with Section E 605.1.3. The calculations shall be based on a single zone with a constant contaminant emission rate. The manufacturer, specifier, or designer of the equivalent ventilation system shall certify that the system is in accordance with this intent and provide supporting documentation.

perated in such a way as to provide the same or lower annual exposure as would be provided in accordance with Section E 605.1.3. The calculations shall be based on a single zone with a constant contaminant emission rate. The manufacturer, specifier, or designer of the equivalent ventilation system shall certify that the system is in accordance with this intent and provide supporting documentation.

[ASHRAE 62.2:4.6] E 605.2 Bathroom Exhaust Fans. Except where a whole house energy recovery system is used, a mechanical exhaust fan vented to the outdoors shall be provided in each room containing a bathtub, shower, or tub/shower combination. The ventilation rate shall be not less than 50 ft [3] /min (0.02 m [3] /s) for intermittent operation and 20 ft [3] /min (0.009 m [3] /s) for continuous operation. Fans shall comply with the Energy Star Program.

E 605.3 Filters. Heating and air conditioning filters shall have a MERV rating of 6 or higher. The air distribution system shall be designed for the pressure drop across the filter.

E 606.0 Indoor Air Quality for Other than Low-Rise Residential Buildings.

E 606.1 Minimum Indoor Air Quality. The building shall comply with Chapter 4 or ASHRAE 62.1 for ventilation air supply.

E 607.0 Environmental Comfort.

E 607.1 Thermal Comfort Controls. The mechanical systems and controls of building shall be designed to provide and maintain indoor comfort conditions in accordance with

ASHRAE 55.

E 607.2 Heating and Air-Conditioning System Design. Heating and air-conditioning systems shall be sized, designed, and have their equipment selected in accordance with the following:

(1) Heat loss and heat gain are established in accordance with ACCA Manual J, ASHRAE handbooks, or other equivalent methods.

(2) Duct systems shall be sized in accordance with ACCA Manual D, ASHRAE handbooks, or other equivalent methods.

(3) Heating and cooling equipment in accordance with ACCA Manual S or other equivalent methods.

E 608.0 Low VOC Solvent Cement and Primer.

E 608.1 General. Primers and solvent cements used to join plastic pipe, and fittings shall be in accordance with Section E 608.1.1 and Section E 608.1.2.

E 608.1.1 Solvent Cement. Solvent cement, including one-step solvent cement, shall have a volatile organic compound (VOC) content of less than or equal to 65 ounces per gallon (oz/gal) (487 g/L) for CPVC cement, 68 oz/gal (509 g/L) for PVC cement, and 43 oz/gal (322 g/L) for ABS cement, as determined by the South Coast Air Quality Management District’s Laboratory Methods of Analysis for Enforcement Samples, Method 316A. E 608.1.2 Primer. Primer shall have a volatile organic compound (VOC) content of less than or equal to 73 oz/gal (546 g/L), as determined by the South Coast Air Quality Management District’s Laboratory Methods of Analysis for Enforcement Samples, Method 316A.

E 701.0 Installer Qualifications.

E 701.1 Scope. The provisions of this section address minimum qualifications of installers of mechanical systems covered within the scope of this appendix.

E 702.0 Qualifications.

E 702.1 General. Where permits are required, the Authority Having Jurisdiction shall have the authority to require contractors, installers, or service technicians to demonstrate competency. Where determined by the Authority Having Jurisdiction, the contractor, installer, or service technician shall be licensed to perform such work.

Part I

E 801.0 Heating, Ventilation, and Air Conditioning Systems Commissioning. E 801.1 Applicability. The provisions of this section apply to the commissioning of commercial and institutional HVAC systems.

E 802.0 Commissioning. E 802.1 Commissioning Requirements. HVAC commissioning shall be included in the design and construction processes of the project to verify that the HVAC systems and components meet the owner’s project requirements and in accordance with this appendix. Commissioning shall be performed in accordance with this appendix by personnel trained and certified in commissioning by a nationally recognized organization. Commissioning requirements shall include the following:

(1) Owner’s project requirements

(2) Basis of design

(3) Commissioning measures shown in the construction doc uments

(4) Commissioning plan

(5) Functional performance

(6) Testing

(7) Post construction documentation and training

(8) Commissioning report

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APPENDIX E

HVAC systems and components covered by this appendix as well as process equipment and controls, and renewable energy systems shall be included in the scope of the commissioning requirements. E 802.2 Owner’s Project Requirements (OPR). The performance goals and requirements of the HVAC system shall be documented before the design phase of the project begins. This documentation shall include not less than the following:

(1) Environmental and sustainability goals

(2) Energy efficiency goals

(3) Indoor environmental quality requirements

(4) Equipment and systems performance goals

(5) Building occupant and O&M personnel expectations E 802.3 Basis of Design (BOD). A written explanation of how the design of the HVAC system meets the owner’s project requirements shall be completed at the design phase of the building project, and updated as necessary during the design and construction phases. The basis of design document shall cover not less than the following systems:

(1) Heating, ventilation, air conditioning (HVAC) systems and controls

(2) Water heating systems

(3) Renewable energy systems E 802.4 Commissioning Plan. A commissioning plan shall be completed to document the approach to how the project will be commissioned, and shall be started during the design phase of the building project. The commissioning plan shall include not less than the following:

(1) General project information

(2) Commissioning goals

(3) Systems to be commissioned. Plans to test systems and components shall include not less than the following:

(a) A detailed explanation of the original design intent.

(b) Equipment and systems to be tested, including the extent of tests.

(c) Functions to be tested.

(d) Conditions under which the test shall be performed.

(e) Measurable criteria for acceptable performance.

(4) Commissioning team information.

(5) Commissioning process activities, schedules, and responsibilities. Plans for the completion of commissioning requirements listed in Section E 802.5 through Section E 802.7 shall be included.

E 802.5 Functional Performance Testing. Functional performance tests shall demonstrate the correct installation and operation of each component, system, and system-to-system interface in accordance with the approved plans and specifications. Functional performance testing reports shall contain information addressing each of the building components tested, the testing methods utilized, and readings and adjustments made.

E 802.6 Post Construction Documentation and Train- ing. A system manual and systems operations training are required.

E 802.6.1 Systems Manual. Documentation of the operational aspects of the HVAC system shall be completed within the systems manual and delivered to the building owner and facilities operator. The systems manual shall include not less than the following:

(1) Site information, including facility description, history, and current requirements.

(2) Site contact information.

(3) Basic O&M, including general site operating procedures, basic troubleshooting, recommended maintenance requirements, and site events log.

(4) Major systems.

(5) Site equipment inventory and maintenance notes.

(6) Equipment/system warranty documentation and information.

(7) “As-Built” design drawings.

(8) Other resources and documentation.

E 802.6.2 Systems Operations Training. The training of the appropriate maintenance staff for each equipment type or system shall include not less than the following:

(1) System/Equipment overview (what it is, what it does, and what other systems or equipment it interfaces with).

(2) Review of the information in the systems manual.

(3) Review of the record drawings on the system/equip ment.

E 802.7 Commissioning Report. A complete report of commissioning process activities undertaken through the design, construction, and post-construction phases of the building project shall be completed and provided to the

owner.

Part II

E 803.0 Commissioning Acceptance.

E 803.1 General. Part II of this appendix provides a means of verifying the commissioning requirements of Section E 802.1. The activities specified in Part II of this appendix includes three aspects, as described as follows:

(1) Visual inspection of the equipment and installation.

(2) Review of the certification requirements.

(3) Functional tests of the systems and controls.

E 803.2 Construction Documents. Details of commissioning acceptance requirements shall be incorporated into the construction documents, including information that describes the details of the functional tests to be performed. This information shall be permitted to be integrated into the specifications for testing and air balancing, energy management and control system, equipment startup procedures or commissioning. It is possible that the work will be performed by a combination of the test and balance (TAB) contractor,

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APPENDIX E

mechanical/electrical contractor, and the energy management control system (EMCS) contractor, so applicable roles and responsibilities shall be clearly called out.

E 803.2.1 Roles and Responsibilities. The roles and responsibilities of the persons involved in commissioning acceptance are included in Section E 803.2.1.1 through Section E 803.2.1.3.

E 803.2.1.1 Field Technician. The field technician shall be responsible for performing and documenting the results of the acceptance procedures on the certificate of acceptance forms. The field technician shall sign the certificate of acceptance to certify that the information he provides on the certificate of acceptance is true and correct.

E 803.2.1.2 Responsible Person. The responsible person shall be the contractor or registered design professional of record. A certificate of acceptance shall be signed by a responsible person to take responsibility for the scope of work specified by the certificate of acceptance document. The responsible person shall perform the field testing and verification work, and where this is the case, the responsible person shall complete and sign both the field technician’s signature block and the responsible person’s signature block on the certificate of acceptance form. The responsible person assumes responsibility for the acceptance testing work performed by the field technician agent or employee. E 803.2.1.3 Certificate of Acceptance. The certificate of acceptance shall be submitted to the Authority Having Jurisdiction in order to receive the final certificate of occupancy. The Authority Having Jurisdiction shall not release a final certificate of occupancy unless the submitted certificate of acceptance demonstrates that the specified systems and equipment have been shown to be performing in accordance with the applicable acceptance requirements. The Authority Having Jurisdiction has the authority to require the field technician and responsible person to demonstrate competence, to its satisfaction. Certificate of acceptance forms are located in Section E 806.0.

submitted certificate of acceptance demonstrates that the specified systems and equipment have been shown to be performing in accordance with the applicable acceptance requirements. The Authority Having Jurisdiction has the authority to require the field technician and responsible person to demonstrate competence, to its satisfaction. Certificate of acceptance forms are located in Section E 806.0.

E 804.0 Commissioning Tests. E 804.1 General. Functional tests shall be performed on new equipment and systems installed in either new construction or retrofit applications in accordance with this section. The appropriate certificate of acceptance form along with each specific test shall be completed and submitted to the Authority Having Jurisdiction before a final occupancy permit can be granted.

E 804.2 Tests. Functional testing shall be performed on the devices and systems listed in this section. The functional test results are documented using the applicable certificate of acceptance forms shown in parenthesis and located in Section E 806.0. The functional tests shall be performed in accordance with Section E 805.0 using the following forms:

(1) Minimum ventilation controls for constant and variable air volume systems (Form MECH-2A).

(2) Zone temperature and scheduling controls for constant volume, single-zone, unitary air conditioner and heat pump systems (Form MECH-3A).

(3) Duct leakage on a subset of small single-zone systems depending on the ductwork location (Form MECH-4A).

(4) Air economizer controls for economizers that are not factory installed and tested (Form MECH-5A).

(5) Demand-controlled ventilation control systems (Form MECH-6A).

(6) Supply fan variable flow controls (Form MECH-7A).

(7) Valve leakage for hydronic variable flow systems and isolation valves on chillers and boilers in plants with more than one chiller or boiler being served by the same primary pumps through a common header (Form MECH8A).

(8) Supply water temperature reset control strategies programmed into the building automation system for water systems (e.g., chilled, hot, or condenser water) (Form MECH-9A).

(9) Hydronic variable flow controls on a water system where the pumps are controlled by variable frequency drives (e.g., chilled and hot water systems; water-loop heat pump systems) (Form MECH-10A).

(10)Automatic demand shed control (Form MECH-11A).

(11)Fault detection and diagnostic for DX units (Form MECH-12A).

(12)Automatic fault detection and diagnostic systems (AFDD) (Form MECH-13A).

(13)Distributed energy storage DEC/DX AC systems (Form MECH-14A).

(14)Thermal energy storage (TES) systems (Form MECH15A). E 804.3 Acceptance Process. The functional testing process shall comply with Section E 804.3.1 through Section E 804.3.4.

E 804.3.1 Plan Review. The installing contractor, registered design professional of record, owner’s agent, or the person responsible for certification of the acceptance testing on the certificate of acceptance (responsible person) shall review the plans and specifications to ensure that they are in accordance with the acceptance requirements. This is typically done prior to signing a certificate of compliance. E 804.3.2 Construction Inspection. The installing contractor, registered design professional of record, owner’s agent, or the person responsible for certification of the acceptance testing on the certificate of acceptance (responsible person) shall perform a construction inspection prior to testing to ensure that the equipment that is installed is capable of complying with the requirements of this appendix and is calibrated. The installation of associated systems and equipment necessary for proper system operation is required to be completed prior to the testing.

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APPENDIX E

E 804.3.3 Acceptance Testing. One or more field technicians shall perform the acceptance testing; identify performance deficiencies; ensure that they are corrected; and where necessary, repeat the acceptance procedures until the specified systems and equipment are performing in accordance with the acceptance requirements. The field technician who performs the testing shall sign the certificate of acceptance to certify the information has been provided to document the results of the acceptance procedures is true and correct.

The responsible person shall review the test results from the acceptance requirement procedures provided by the field technician and sign the certificate of acceptance to certify compliance with the acceptance requirements. The responsible person shall be permitted to perform the field technician’s responsibilities, and shall then sign the field technician declaration on the certificate of acceptance to certify that the information on the form is true and correct.

E 804.3.4 Certificate of Occupancy. The Authority Having Jurisdiction shall not issue the final certificate of occupancy until required certificates of acceptance are submitted. Copies of completed, signed certificates of acceptance are required to be posted, or made available with the permit(s), and shall be made available to the Authority Having Jurisdiction.

E 805.0 HVAC System Tests.

E 805.1 Variable Air Volume Systems (Form MECH- 2A). This test ensures that adequate outdoor air ventilation is provided through the variable air volume air handling unit at two representative operating conditions. The test consists of measuring outdoor air values at maximum flow and at or near minimum flow. The test verifies that the minimum volume of outdoor air is introduced to the air handling unit where the system is in occupied mode at these two conditions of supply airflow. This test shall be performed in conjunction with supply fan variable flow controls test procedures to reduce the overall system testing time as both tests use the same two conditions of airflow for their measurements.

E 805.1.1 Test Procedure. The procedure for performing a functional test for variable air volume systems shall be in accordance with Section E 805.1.1.1 and Sec tion E 805.1.1.2.

E 805.1.1.1 Construction Inspection. Prior to functional testing, verify and document that the system controlling outside airflow is calibrated either in the field or factory.

E 805.1.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Where the system has an outdoor air economizer, force the economizer high limit to disable economizer control (e.g., for a fixed dry-bulb high limit, lower the setpoint below the current outdoor air temperature).

Step 2: Adjust supply airflow to either the sum of the minimum zone airflows or 30 percent of the total design airflow. Verify and document the following:

(1) Measured outside airflow reading is within 10 percent of the total ventilation air called for in the certificate of compliance.

(2) OSA controls stabilize within 5 minutes.

Step 3: Adjust supply airflow to achieve design airflow. Verify and document the following:

(1) Measured outside airflow reading is within 10 percent of the total ventilation air called for in the certificate of compliance.

(2) OSA controls stabilize within 5 minutes.

Step 4: Restore system to “as-found” operating conditions.

E 805.1.2 Acceptance Criteria. System controlling outdoor air flow shall be calibrated in the field or at the factory.

Measured outdoor airflow reading shall be within 10 percent of the total value found on the certificate of compliance under the following conditions:

(1) Minimum system airflow.

(2) Thirty percent of total design flow design supply airflow.

E 805.2 Constant Volume Systems (Form MECH-2A). The purpose of this test is to ensure that adequate outdoor air ventilation is provided through the constant volume air handling unit to the spaces served under operating conditions. The intent of this test is to verify that the minimum volume of outdoor air is introduced to the air handling unit during typical space occupancy.

E 805.2.1 Test Procedure. The procedure for performing a functional test for constant air volume systems shall be in accordance with Section E 805.2.1.1 and Sec tion E 805.2.1.2.

E 805.2.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

(1) Minimum position is marked on the outside air damper.

(2) The system has means of maintaining the minimum outdoor air damper position.

E 805.2.1.2 Functional Testing. Where the system has an outdoor air economizer, force the economizer to the minimum position and stop outside air damper modulation (e.g., for a fixed dry-bulb high limit, lower the setpoint below the current outdoor air temperature).

E 805.2.2 Acceptance Criteria. The system has a means of maintaining the minimum outdoor air damper position. The minimum damper position is marked on the outdoor air damper. The measured outside airflow reading shall be within 10 percent of the total ventilation air called for in the certificate of compliance.

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E 805.3 Constant Volume, Single-Zone, Unitary Air Conditioner and Heat Pumps Systems Acceptance (Form MECH-3A). The purpose of this test is to verify the individual components of a constant volume, single-zone, unitary air conditioner and heat pump system function correctly; including: thermostat installation and programming, supply fan, heating, cooling, and damper operation.

E 805.3.1 Test Procedure. The procedure for performing a functional test for constant volume, singlezone, unitary air conditioner and heat pump systems shall be in accordance with Section E 805.3.1.1 and Section E

805.3.1.2.

E 805.3.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

(1) Thermostat is located within the space-conditioning zone that is served by the HVAC sys tem.

(2) Thermostat shall be in accordance with temperature adjustment and dead band requirements.

(3) Occupied, unoccupied, and holiday schedules shall be programmed per the facility’s schedule.

(4) Preoccupancy purge is programmed.

E 805.3.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Disable economizer and demand control ventilation systems (where applicable).

Step 2: Simulate a heating demand during the occupied condition. Verify and document the following:

(1) Supply fan operates continually.

(2) The unit provides heating.

(3) No cooling is provided by the unit.

(4) Outside air damper is at minimum position.

Step 3: Simulate operation in the dead band during occupied condition. Verify and document the following:

(1) Supply fan operates continually.

(2) Neither heating nor cooling is provided by the unit.

(3) Outside air damper is at minimum position.

Step 4: Simulate cooling demand during occupied condition. Lock out economizer (where applicable). Verify and document the following:

(1) Supply fan operates continually.

(2) The unit provides cooling.

(3) No heating is provided by the unit.

(4) Outside air damper is at minimum position.

Step 5: Simulate operation in the dead band during unoccupied mode. Verify and document the following:

(1) Supply fan is off.

(2) Outside air damper is fully closed.

(3) Neither heating nor cooling is provided by the unit.

Step 6: Simulate heating demand during unoccupied conditions. Verify and document the following:

(1) Supply fan is on (either continuously or cycling).

(2) Heating is provided by the unit.

(3) No cooling is provided by the unit.

(4) Outside air damper is either closed or at minimum position.

Step 7: Simulate cooling demand during unoccupied condition. Lock out economizer (where applicable). Verify and document the following:

(1) Supply fan is on (either continuously or cycling).

(2) Cooling is provided by the unit.

(3) No heating is provided by the unit.

(4) Outside air damper is either closed or at minimum position.

Step 8: Simulate manual override during unoccupied condition. Verify and document the following:

(1) System operates in “occupied” mode.

(2) System reverts to “unoccupied” mode where manual override time period expires.

Step 9: Restore economizer and demand control ventilation systems (where applicable), and remove system overrides initiated during the test.

E 805.3.2 Acceptance Criteria. Thermostat is located within the space-conditioning zone that is served by the respective HVAC system. The thermostat shall comply with temperature adjustment and dead band requirements. Occupied, unoccupied, and holiday schedules shall be programmed per the facility’s schedule. Preoccupancy purge is programmed in accordance with the requirements.

E 805.4 Air Distribution Systems (Form MECH-4A). The purpose of this test is to verify duct work associated with non-exempt constant volume, single-zone, HVAC units (e.g., air conditioners, heat pumps, and furnaces) meet the material, installation, and insulation R-values and leakage requirements outlined in this appendix. This test is required for single-zone units serving less than 5000 square feet (464.52 m [2] ) of floor area where 25 percent or more of the duct surface area is in one of the following spaces:

(1) Outdoors.

(2) In a space directly under a roof where the U-factor of the roof is greater than the U-factor of the ceiling.

(3) In a space directly under a roof with fixed vents or openings to the outside or unconditioned spaces.

(4) In an unconditioned crawl space.

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APPENDIX E

(5) In other unconditioned spaces.

This test applies to both new duct systems and to existing duct systems being extended or the space conditioning system is altered by the installation or replacement of space conditioning equipment, including: replacement of the air handler; outdoor condensing unit of a split system air conditioner or heat pump; cooling or heating coil; or the furnace heat exchanger. Existing duct systems do not have to be tested where they are insulated or sealed with asbestos. E 805.4.1 Test Procedure. The procedure for performing a functional test for air distribution systems shall be in accordance with Section E 805.4.1.1 and Section E

805.4.1.2.

E 805.4.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

(1) Duct connections shall comply with the requirements of this appendix and this code.

(2) Flexible ducts are not compressed.

(3) Ducts are fully accessible for testing.

(4) Joints and seams are properly sealed in accordance with the requirements of this appendix.

(5) Insulation R-Values shall comply with the minimum requirements of this appendix. E 805.4.1.2 Functional Testing. Perform duct leakage test in accordance with Section E 503.4.7.2.1.

E 805.4.2 Acceptance Criteria. Flexible ducts are not compressed or constricted. Duct connections shall comply with the requirements of this appendix and this code (new ducts only). Joints and seams are properly sealed in accordance with the requirements of this appendix and this code (new ducts only). Duct R-values shall comply with the minimum requirements of this appendix (new ducts only). Insulation is protected from damage and suitable for outdoor usage where applicable (new ducts only). The leakage shall not exceed the rate in accordance with Section E 503.4.7.2.1.

E 805.5 Air Economizer Controls Acceptance (Form MECH-5A). The purpose of functionally testing an air economizer cycle is to verify that an HVAC system uses outdoor air to satisfy space cooling loads where outdoor air conditions are acceptable. There are two types of economizer controls; stand-alone packages and DDC controls. The stand-alone packages are commonly associated with small unitary rooftop HVAC equipment, and DDC controls are typically associated with built-up or large packaged air handling systems. Test procedures for both economizer control types are provided.

For units with economizers that are factory installed and certified operational by the manufacturer to economizer quality control requirements, the in-field economizer functional tests do not have to be conducted. A copy of the manufacturer’s certificate shall be attached to the Form MECH-5A. However, the construction inspection, including compliance with high-temperature lockout temperature setpoint, shall be completed regardless of whether the economizer is field or factory installed.

E 805.5.1 Test Procedure. The procedure for performing a functional test for air economizer controls shall comply with Section E 805.5.1.1 and Section E 805.5.1.2.

E 805.5.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

(1) Economizer lockout setpoint is in accordance with this appendix.

(2) Economizer lockout control sensor is located to prevent false readings.

(3) System is designed to provide up to 100 percent outside air without over-pressurizing the building.

(4) For systems with DDC controls lockout sensor(s) are either factory calibrated or field calibrated.

(5) For systems with non-DDC controls, manufacturer’s startup and testing procedures are applied.

E 805.5.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Disable demand control ventilation systems (where applicable).

Step 2: Enable the economizer, and simulate a cooling demand large enough to drive the economizer fully open. Verify and document the following:

(1) Economizer damper is 100 percent opened and return air damper is 100 percent closed.

(2) Where applicable, verify that the economizer remains 100 percent open where the cooling demand can no longer be met by the economizer alone.

(3) Applicable fans and dampers operate as intended to maintain building pressure.

(4) The unit heating is disabled.

Step 3: Disable the economizer and simulate a cooling demand. Verify and document the following:

(1) Economizer damper shall close to its minimum position.

(2) Applicable fans and dampers shall operate as intended to maintain building pressure.

(3) The unit heating is disabled.

Step 4: Simulate a heating demand, and set the economizer so that it is capable of operating (e.g., actual outdoor air conditions are below lockout setpoint). Verify the economizer is at minimum position.

Step 5: Restore demand control ventilation systems (where applicable) and remove system overrides initiated during the test.

E 805.5.2 Acceptance Criteria. Air economizer controls acceptance criteria shall be as follows:

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APPENDIX E

(1) Where the economizer is factory installed and certified, a valid factory certificate is required for acceptance. No additional equipment tests are necessary.

(2) Air economizer lockout setpoint is in accordance with this appendix. Outside sensor location accurately reads true outdoor air temperature and is not affected by exhaust air or other heat sources.

(3) Sensors are located to achieve the desired control.

(4) During economizer mode, the outdoor air damper shall modulate open to a maximum position and return air damper to 100 percent closed.

(5) The outdoor air damper is 100 percent open before mechanical cooling is enabled and for units 75 000 Btu/h (22 kw) and larger remains at 100 percent open while mechanical cooling is enabled (economizer integration where used for compliance).

(6) Where the economizer is disabled, the outdoor air damper closes to a minimum position; the return damper modulates 100 percent open, and mechanical cooling remains enabled. E 805.6 Demand-Controlled Ventilation Systems Acceptance (Form MECH-6A). The purpose of this test is to verify that systems required to employ demand-controlled ventilation shall be permitted to vary outside ventilation flow rates based on maintaining interior carbon dioxide (CO 2 ) concentration setpoints. Demand-controlled ventilation refers to an HVAC system’s ability to reduce outdoor air ventilation flow below design values where the space served is at less than design occupancy. Carbon dioxide is a good indicator of occupancy load and is the basis used for modulating ventilation flow rates.

E 805.6.1 Test Procedure. The procedure for performing a functional test for demand-control ventilation (DVC) systems shall be in accordance with Section E 805.6.1.1 and Section E 805.6.1.2.

E 805.6.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

(1) Carbon dioxide control sensor is factory calibrated or field-calibrated in accordance with this appendix.

(2) The sensor is located in the high-density space between 3 feet (914 mm) and 6 feet (1829 mm) above the floor or at the anticipated level of the occupants’ heads.

(3) DCV control setpoint is at or below the carbon dioxide concentration permitted by this appendix.

E 805.6.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Disable economizer controls.

Step 2: Simulate a signal at or slightly above the carbon dioxide concentration setpoint required by this appendix. Verify and document the following:

(1) For single zone units, outdoor air damper modulates open to satisfy the total ventilation air called for in the certificate of compliance.

(2) For multiple zone units, either outdoor air damper or zone damper modulate open to satisfy the zone ventilation requirements.

Step 3: Simulate signal well below the carbon dioxide setpoint. Verify and document the following:

(1) For single zone units, outdoor air damper modulates to the design minimum value.

(2) For multiple zone units, either outdoor air damper or zone damper modulate to satisfy the reduced zone ventilation requirements.

Step 4: Restore economizer controls and remove system overrides initiated during the test.

Step 5: With controls restored, apply carbon dioxide calibration gas at a concentration slightly above the setpoint to the sensor. Verify that the outdoor air damper modulates open to satisfy the total ventilation air called for in the certificate of compliance.

E 805.6.2 Acceptance Criteria. Demand-controlled ventilation systems acceptance criteria shall be as follows:

(1) Each carbon dioxide sensor is factory calibrated (with calibration certificate) or field calibrated.

(2) Each carbon dioxide sensor is wired correctly to the controls to ensure proper control of the outdoor air damper.

(3) Each carbon dioxide sensor is located correctly within the space 1 foot (305 mm) to 6 feet (1829 mm) above the floor.

(4) Interior carbon dioxide concentration setpoint is not more than 600 parts per million (ppm) plus outdoor air carbon dioxide value where dynamically measured or not more than 1000 ppm where no OSA sensor is provided.

(5) A minimum OSA setting is provided where the system is in occupied mode in accordance with this appendix regardless of space carbon dioxide readings.

(6) A maximum OSA damper position for DCV control shall be established in accordance with this appendix, regardless of space carbon dioxide readings.

(7) The outdoor air damper shall modulate open where the carbon dioxide concentration within the space exceeds setpoint.

(8) The outdoor air damper modulates closed (toward minimum position) where the carbon dioxide concentration within the space is below setpoint.

E 805.7 Supply Fan Variable Flow Controls (Form MECH-7A). The purpose of this test is to ensure that the supply fan in a variable air volume application modulates to meet system airflow demand. In most applications, the individual VAV boxes serving each space will modulate the amount of

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APPENDIX E

air delivered to the space based on heating and cooling requirements. As a result, the total supply airflow provided by the central air handling unit shall vary to maintain sufficient airflow through each VAV box. Airflow shall be controlled using a variable frequency drive (VFD) to modulate supply fan speed and vary system airflow. The most common strategy for controlling the VFD is to measure and maintain static pressure within the duct.

E 805.7.1 Test Procedure. The procedure for performing a functional test for supply fan variable controls shall be in accordance with Section E 805.7.1.1 and Sec tion E 805.7.1.2.

E 805.7.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

(1) Supply fan controls modulate to increase capacity.

(2) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating set point.

(3) Supply fan controls stabilize within a 5 minute period.

E 805.7.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Simulate demand for design airflow. Verify and document the following:

(1) Supply fan controls modulate to increase capacity.

(2) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating set point. (3) Supply fan controls stabilize within a 5 minute period. Step 2: Simulate demand for minimum airflow. Verify and document the following: (1) Supply fan controls modulate to decrease capacity. (2) Current operating setpoint has decreased (for systems with DDC to the zone level). (3) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating setpoint. (4) Supply fan controls stabilize within a 5 minute period. Step 3: Restore system to correct operating conditions.

E 805.7.2 Acceptance Criteria. Supply fan variable flow controls acceptance criteria shall be as follows: (1) Static pressure sensor(s) is factory calibrated (with calibration certificate) or field calibrated. (2) For systems without DDC controls to the zone level, the pressure sensor setpoint is less than one-third of the supply fan design static pressure.

(3) For systems with DDC controls with VAV boxes reporting to the central control panel, the pressure setpoint is reset by zone demand (box damper position or a trim and respond algorithm).

At full flow:

(1) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating control static pressure setpoint. (2) Supply fan controls stabilizes within a 5 minute period. (3) At minimum flow (not less than 30 percent of total design flow). (4) Supply fan controls modulate to decrease capacity. (5) Current operating setpoint has decreased (for systems with DDC to the zone level). (6) Supply fan maintains discharge static pressure within plus or minus 10 percent of the current operating setpoint. E 805.8 Valve Leakage (Form MECH-8A). The purpose of this test is to ensure that control valves serving variable flow systems are designed to withstand the pump pressure over the full range of operation. Valves with insufficient actuators will lift under certain conditions causing water to leak through and loss of control. This test applies to the variable flow systems, chilled and hot-water variable flow systems, chiller isolation valves, boiler isolation valves, and watercooled air conditioner and hydronic heat pump systems.

E 805.8.1 Test Procedure. The procedure for performing a functional test for valve leakage shall be in accordance with Section E 805.8.1.1 and Section E

805.8.1.2.

E 805.8.1.1 Construction Inspection. Prior to functional testing, verify and document the valve and piping arrangements were installed in accordance with the design drawings. E 805.8.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: For each pump serving the distribution system, dead head the pumps using the discharge isolation valves at the pumps. Document the following:

(1) Record the differential pressure across the

pumps.

(2) Verify that this is within 5 percent of the submittal data for the pump.

Step 2: Reopen the pump discharge isolation valves. Automatically close valves on the systems being tested. Where three-way valves are present, close off the bypass line. Verify and document the following:

(1) The valves automatically close.

(2) Record the pressure differential across the

pump.

(3) Verify that the pressure differential is within 5 percent of the reading from Step 1 for the pump that is operating during the valve test.

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APPENDIX E

Step 3: Restore system to correct operating conditions.

E 805.8.2 Acceptance Criteria. System has no flow where coils are closed and the pump is turned on. E 805.9 Supply Water Temperature Reset Controls (Form MECH-9A). The purpose of this test is to ensure that both the chilled water and hot water supply temperatures are automatically reset based on either building loads or outdoor air temperature, as indicated in the control sequences. Many HVAC systems are served by central chilled and heating hot water plants. The supply water operating temperatures shall meet peak loads where the system is operating at design conditions. As the loads vary, the supply water temperatures shall be permitted to be adjusted to satisfy the new operating conditions. The chilled water supply temperature shall be permitted to be raised as the cooling load decreases, and heating hot water supply temperature shall be permitted to be lowered as the heating load decreases.

This requirement applies to chilled and hot water systems that are not designed for variable flow, and that have a design capacity greater than or equal to 500 000 Btu/h (147 kW).

E 805.9.1 Test Procedure. The procedure for performing a functional test for supply water temperature reset controls shall be in accordance with Section E

805.9.1.1 and Section E 805.9.1.2.

E 805.9.1.1 Construction Inspection. Prior to functional testing, verify and document the supply water temperature sensors shall be either factory or field calibrated.

E 805.9.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Change reset control variable to its maximum value. Verify and document the following:

(1) Chilled or hot water temperature setpoint is reset to appropriate value.

(2) Actual supply temperature changes to meet setpoint.

(3) Verify that supply temperature is within 2 percent of the control setpoint.

Step 2: Change reset control variable to its minimum value. Verify and document the following:

(1) Chilled or hot water temperature setpoint is reset to appropriate value.

(2) Actual supply temperature changes to meet setpoint.

(3) Verify that supply temperature is within 2 percent of the control setpoint.

Step 3: Restore reset control variable to automatic control. Verify and document the following:

(1) Chilled or hot water temperature setpoint is reset to appropriate value.

(2) Actual supply temperature changes to meet setpoint.

(3) Verify that supply temperature is within 2 percent of the control setpoint.

E 805.9.2 Acceptance Criteria. The supply water temperature sensors are either factory calibrated (with calibration certificates) or field-calibrated. Sensor performance shall comply with the specifications. The supply water reset is operational.

E 805.10 Hydronic System Variable Flow Controls (Form MECH-10A). The purpose of this test is to ensure that hydronic variable flow chilled water and water-loop heat pump systems with circulating pumps larger than 5 hp (3.7 kW) vary system flow rate by modulating pump speed using a variable frequency drive (VFD) or equivalent. As the loads within the building fluctuate, control valves modulate the amount of water passing through each coil and add or remove the desired amount of energy from the air stream to satisfy the load. In the case of water-loop heat pumps, each two-way control valve associated with a heat pump will be closed where that unit is not operating. As each control valve modulates, the pump variable frequency drive (VFD) responds accordingly to meet system water flow requirements. This is not required on heating hot water systems with variable flow designs or for condensing water serving water cooled chillers. E 805.10.1 Test Procedure. The procedure for performing a functional test for hydronic system variable flow controls shall be in accordance with Section E

805.10.1.1 and Section E 805.10.1.2.

E 805.10.1.1 Construction Inspection. Prior to functional testing, verify and document the pressure sensors are either factory or field calibrated. E 805.10.1.2 Functional Testing. The functional testing shall comply with the following steps:

Step 1: Open control valves to increase water flow to not less than 90 percent design flow. Verify and document the following:

(1) Pump speed increases.

(2) System pressure is either within plus or minus 5 percent of current operating setpoint, or the pressure is below the setpoint, and the pumps are operating at 100 percent speed.

(3) System operation shall stabilize within 5 minutes after test procedures are initiated.

Step 2: Modulate control valves to reduce water flow to 50 percent of the design flow or less, but not lower than the pump minimum flow. Verify and document the following:

(1) Pump speed decrease.

(2) Current operating setpoint has decreased (for systems with DDC to the zone level).

(3) Current operating setpoint has not increased (for all other systems).

(4) System pressure is within 5 percent of current operating setpoint.

(5) System operation stabilizes within 5 minutes after test procedures are initiated.

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APPENDIX E

E 805.10.2 Acceptance Criteria. The differential pressure sensor is either factory calibrated (with calibration certificates) or field calibrated. The pressure sensor shall be located at or near the most remote HX or control valve. The setpoint system controls shall stabilize.

E 805.11 Automatic Demand Shed Control (Form MECH-11A). The purpose of this test is to ensure that the central demand shed sequences have been properly programmed into the DDC system.

E 805.11.1 Test Procedure. The procedure for performing a functional test for automatic demand shed controls shall be in accordance with Section E 805.11.1.1

and Section E 805.11.1.2.

E 805.11.1.1 Construction Inspection. Prior to functional testing, verify and document that the EMCS interface enables activation of the central

demand shed controls.

E 805.11.1.2 Functional Testing. The functional testing shall comply with the following steps:

Step 1: Engage the global demand shed system. Verify and document the following:

(1) That the cooling setpoint in noncritical spaces increases by the proper amount.

(2) That the cooling setpoint in critical spaces do not change.

Step 2: Disengage the global demand shed system. Verify and document the following:

(1) That the cooling setpoint in noncritical spaces return to their original values.

(2) That the cooling setpoint in critical spaces do not change.

E 805.11.2 Acceptance Criteria. The control system changes the setpoints of noncritical zones on activation of a single central hardware or software point then restores the initial setpoints where the point is released.

E 805.12 Fault Detection and Diagnostics (FDD) for Packaged Direct-Expansion (DX) Units (Form MECH-12A). The purpose of this test is to verify proper fault detection and reporting for automated fault detection and diagnostics systems for packaged units. Automated FDD systems ensure proper equipment operation by identifying and diagnosing common equipment problems such as improper refrigerant charge, low airflow, or faulty economizer operation. Qualifying FDD systems receive a compliance credit where using the performance approach. A system that does not meet the eligibility requirements shall be permitted to be installed, but no compliance credit will be given.

E 805.12.1 Test Procedure. The procedure for performing a functional test for fault detection and diagnostics (FDD) for packaged direct-expansion (DX) units shall be in accordance with Section E 805.12.1.1 and

Section E 805.12.1.2.

E 805.12.1.1 Construction Inspection. Prior to functional testing, verify and document that the FDD

hardware is installed on equipment by the manufacturer, and that equipment make and model include factory-installed FDD hardware that match the information indicated on copies of the manufacturer’s cut sheets and on the plans and specifications.

This procedure applies to fault detection and diagnostics (FDD) system for direct-expansion packaged units containing the following features:

(1) The unit shall include a factory-installed economizer and shall limit the economizer dead band to not more than 2°F (-17°C).

(2) The unit shall include direct-drive actuators on outside air and return air dampers.

(3) The unit shall include an integrated economizer with either differential dry-bulb or differential enthalpy control.

(4) The unit shall include a low temperature lockout on the compressor to prevent coil freeze-up or comfort problems.

(5) Outside air and return air dampers shall have maximum leakage rates in accordance to this appendix.

(6) The unit shall have an adjustable expansion control device such as a thermostatic expansion valve (TXV).

(7) To improve the ability to troubleshoot charge and compressor operation, a high-pressure refrigerant port will be located on the liquid line. A low-pressure refrigerant port will be located on the suction line.

(8) The following sensors shall be permanently installed to monitor system operation, and the controller shall have the capability of displaying the value of each parameter:

(a) Refrigerant suction pressure

(b) Refrigerant suction temperature

(c) Liquid line pressure

(d) Liquid line temperature

(e) Outside air temperature

(f) Outside air relative humidity

(g) Return air temperature

(h) Return air relative humidity

(i) Supply air temperature

(j) Supply air relative humidity

The controller will provide system status by indicating the following conditions:

(1) Compressor enabled

(2) Economizer enabled

(3) Free cooling available

(4) Mixed air low limit cycle active

(5) Heating enabled

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APPENDIX E

The unit controller shall have the capability to manually initiate each operating mode so that the operation of compressors, economizers, fans, and heating system can be independently tested and verified.

E 805.12.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Test low airflow condition by replacing the existing filter with a dirty filter or appropriate obstruction.

Step 2: Verify that the fault detection and diagnostics system reports the fault.

Step 3: Verify that the system is able to verify the correct refrigerant charge.

Step 4: Calibrate outside air, return air, and supply air temperature sensors. E 805.12.2 Acceptance Criteria. The system is able to detect a low airflow condition and report the fault. The system is able to detect where refrigerant charge is low or high and the fault is reported. E 805.13 Automatic Fault Detection Diagnostics (FDD) for Air Handling Units (AHU) and Zone Termi- nal Units (Form MECH-13A). The purpose of this test is to verify that the system detects common faults in air handling units and terminal units. FDD systems for air handling units and zone terminal units require DDC controls to the zone level. Successful completion of this test provides a compliance credit where using the performance approach. An FDD system that does not pass this test shall be permitted to be installed, but no compliance credit will be given. E 805.13.1 Test Procedure. The procedure for performing a functional test for automatic fault detection diagnostics (FDD) for air handling units and zone terminal units shall be in accordance with Section E 805.13.1.1.

E 805.13.1.1 Functional Testing. The functional testing shall be in accordance with Section E 805.13.1.1.1 and Section E 805.13.1.1.2.

E 805.13.1.1.1 Functional Testing for Air Handling Units. The functional testing of AHU with FDD controls shall be in accordance with the following steps:

Step 1: Sensor drift/failure:

(1) Disconnect outside air temperature sensor from unit controller.

(2) Verify that the FDD system reports a fault.

(3) Connect OAT sensor to the unit controller.

(4) Verify that FDD indicates normal system operation.

Step 2: Damper/actuator fault:

(1) From the control system workstation, command the mixing box dampers to full open (100 percent outdoor air).

(2) Disconnect power to the actuator and verify that a fault is reported at the control workstation.

(3) Reconnect power to the actuator and command the mixing box dampers to full open.

(4) Verify that the control system does not report a fault.

(5) From the control system workstation, command the mixing box dampers to a fullclosed position (0 percent outdoor air).

(6) Disconnect power to the actuator and verify that a fault is reported at the control workstation.

(7) Reconnect power to the actuator and command the dampers closed.

(8) Verify that the control system does not report a fault during normal operation.

Step 3: Valve/actuator fault:

(1) From the control system workstation, command the heating and cooling coil valves to full open or closed, then disconnect power to the actuator and verify that a fault is reported at the control workstation.

Step 4: Inappropriate simultaneous heating, mechanical cooling, and economizing or all functions:

(1) From the control system workstation, override the heating coil valve and verify that a fault is reported at the control workstation.

(2) From the control system workstation, override the cooling coil valve and verify that a fault is reported at the control workstation.

(3) From the control system workstation, override the mixing box dampers and verify that a fault is reported at the control workstation.

E 805.13.1.1.2 Functional Testing for Zone Terminal Units. The functional testing of one of each type of terminal unit (VAV box) in the project not less than 5 percent of the terminal boxes shall be in accordance with the following steps:

Step 1: Sensor drift/failure:

(1) Disconnect the tubing to the differential pressure sensor of the VAV box.

(2) Verify that control system detects and reports the fault.

(3) Reconnect the sensor and verify proper sensor operation.

(4) Verify that the control system does not report a fault.

Step 2: Damper/actuator fault:

(1) Damper stuck open.

(a) Command the damper to full open (room temperature above setpoint).

(b) Disconnect the actuator to the damper.

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APPENDIX E

(c) Adjust the cooling setpoint so that the room temperature is below the cooling setpoint to command the damper to the minimum position. Verify that the control system reports a fault. (d) Reconnect the actuator and restore to normal operation. (2) Damper stuck closed. (a) Set the damper to the minimum position.

(b) Disconnect the actuator to the damper.

(c) Set the cooling setpoint below the room temperature to simulate a call for cooling. Verify that the control system reports a fault.

(d) Reconnect the actuator and restore to normal operation.

Step 3: Valve/actuator fault (for systems with hydronic reheat):

(1) Command the reheat coil valve to full

open.

(2) Disconnect power to the actuator. Set the heating setpoint temperature to be lower than the current space temperature, to command the valve closed. Verify that the fault is reported at the control workstation.

(3) Reconnect the actuator and restore normal operation.

Step 4: Feedback loop tuning fault (unstable airflow):

(1) Set the integral coefficient of the box controller to a value 50 times the current value.

(2) The damper cycles continuously and airflow is unstable. Verify that the control system detects and reports the fault.

(3) Reset the integral coefficient of the controller to the original value to restore normal operation.

Step 5: Disconnected inlet duct:

(1) From the control system workstation, command the damper to full closed; then disconnect power to the actuator, and verify that a fault is reported at the control workstation.

E 805.13.2 Acceptance Criteria. The system is able to detect common faults with air-handling units, such as a sensor failure, a failed damper, an actuator, or an improper operating mode.

The system is able to detect and report common faults with zone terminal units, such as a failed damper, an actuator, or a control tuning issue.

E 805.14 Distributed Energy Storage DX AC System (Form MECH-14A). The purpose of this test is to verify the proper operation of distributed energy storage DX systems.

Distributed energy systems (DES) reduce peak demand by operating during off-peak hours and storing cooling, usually in the form of ice. During peak cooling hours the ice is melted to avoid compressor operation. The system typically consists of a water tank containing refrigerant coils that cool the water and convert it to ice. As with a standard direction expansion (DX) air conditioner, the refrigerant is compressed in a compressor and then cooled in an air-cooled condenser. The liquid refrigerant then is directed through the coils in the water tank to make ice or to air handler coils to cool the building. This applies to constant or variable volume, direct expansion (DX) systems with distributed energy storage (DES/DXAC). E 805.14.1 Test Procedure. The procedure for performing a functional test for distributed energy storage DX AC systems shall be in accordance with Section E 805.14.1.1 through Section E 805.14.1.3. E 805.14.1.1 Construction Inspection. Prior to functional testing, verify and document the following:

(1) The water tank is filled to the proper level.

(2) The water tank is sitting on a foundation with adequate structural strength.

(3) The water tank is insulated and the top cover is in place.

(4) The DES/DXAC is installed correctly (e.g., refrigerant piping, etc.).

(5) Verify that the correct model number is installed and configured. E 805.14.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Simulate cooling load during daytime period (e.g., by setting time schedule to include actual time and placing thermostat cooling setpoint below actual temperature). Verify and document the following:

(1) Supply fan operates continually.

(2) Where the DES/DXAC has cooling capacity, DES/DXAC shall run to meet the cooling demand (in ice melt mode).

(3) Where the DES/DXAC has no ice and there is a call for cooling, the DES/DXAC shall run in direct cooling mode.

Step 2: Simulate no cooling load during daytime condition. Verify and document the following:

(1) Supply fan operates in accordance with the facility thermostat or control system.

(2) The DES/DXAC and the condensing unit do not run.

Step 3: Simulate no cooling load during morning shoulder time period. Verify and document the following:

(1) The DES/DXAC is idle.

Step 4: Simulate a cooling load during morning shoulder time period. Verify and document the following:

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APPENDIX E

(1) The DES/DXAC runs in direct cooling mode. E 805.14.1.3 Calibrating Controls. Set the proper time and date in accordance with the manufacturer’s instructions for approved installers. E 805.14.2 Acceptance Criteria. Distributed energy storage DXAC system acceptance criteria shall be as follows:

(1) Verify night time ice making operation.

(2) Verify that tank discharges during on-peak cooling periods.

(3) Verify that the compressor does not run and the tank does not discharge where there is no cooling demand during on-peak periods.

(4) Verify that the system does not operate during a morning shoulder period where there is no cooling demand.

(5) Verify that the system operates in direct mode (with compressor running) during the morning shoulder time period. E 805.15 Thermal Energy Storage (TES) System (Form MECH-15A). The purpose of this test is to verify the proper operation of thermal energy storage (TES) systems. TES systems reduce energy consumption during peak demand periods by shifting energy consumption to nighttime. Operation of the thermal energy storage compressor during the night produces cooling energy which is stored in the form of cooled fluid or ice in tanks. During peak cooling hours the thermal storage is used for cooling to prevent the need for chiller operation. This section is limited to the following types of TES systems:

(1) Chilled water storage

(2) Ice-on-coil

(3) Ice harvester

(4) Brine

(5) Ice-slurry

(6) Eutectic salt

(7) Clathrate hydrate slurry (CHS)

E 805.15.1 Test Procedure. The procedure for performing a functional test for thermal energy storage (TES) system shall be in accordance with Section E 805.15.1.1 and Section E 805.15.1.2.

E 805.15.1.1 Construction Inspection. Prior to functional testing, verify and document the following for the chiller and storage tank:

(1) Chiller:

(a) Brand and Model

(b) Type (centrifugal, reciprocating, other)

(c) Capacity (tons) (SIZE)

(d) Starting efficiency (kW/ton) at beginning of ice production (COMP - kW/TON START)

(e) Ending efficiency (kW/ton) at end of ice production (COMP - kW/TON/END)

(f) Capacity reduction (percent/°F) (PER – COMP - REDUCT/F)

(g) Verify that the efficiency of the chiller meets or exceeds the requirements of Section E 501.0.

(2) Storage Tank:

(a) Storage type (TES-TYPE)

(b) Number of tanks (SIZE)

(c) Storage capacity per tank (ton-hours) (SIZE)

(d) Storage rate (tons) (COOL – STORE RATE)

(e) Discharge rate (tons) (COOL – SUPPLY RATE)

(f) Auxiliary power (watts) (PUMPS + AUX kW)

(g) Tank area (CTANK – LOSS - COEFF)

(h) Tank insulation (R-Value) (CTANK – LOSS – COEFF)

(3) TES System:

(a) The TES system is one of the above eligible systems.

(b) Initial charge rate of the storage tanks (tons).

(c) Final charge rate of the storage tank (tons).

(d) Initial discharge rate of the storage tanks (tons).

(e) Final discharge rate of the storage tank (tons).

(f) Charge test time (hrs).

(g) Discharge test time (hrs).

(h) Tank storage capacity after charge (tonhrs).

(i) Tank storage capacity after discharge (tonhrs).

(j) Tank standby storage losses (UA).

(k) Initial chiller efficiency (kW/ton) during charging.

(l) Final chiller efficiency (kW/ton) during charging.

E 805.15.1.2 Functional Testing. The functional testing shall be in accordance with the following steps:

Step 1: Verify that the TES system and the chilled water plant is controlled and monitored by an energy management system (EMS).

Step 2: Force the time to be between 9:00 p.m. and 9:00 a.m., and simulate a partial or no charge of the tank. Simulate no cooling load by setting the indoor temperature setpoint(s) higher than the ambient temperature.

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APPENDIX E

Where the tank is full or nearly full of ice, it shall be permitted to adjust the control settings for this test. In some cases, the control system will not permit the chiller to start the ice-making process unless a portion of the ice has been melted. The controls designer shall be permitted to use an inventory meter (a 4-20 mA sensor that indicates water level) to determine whether or not ice-making can commence (e.g., not allow ice-making unless the inventory meter signal is less than 17 mA). Where this is the case, this limit can be reset to 20 mA during testing to allow ice making to occur.

Verify that the TES system starts charging (storing energy). This shall be checked by verifying flow and inlet and outlet temperatures of the storage tank, or directly by reading an inventory meter where the system has one.

Step 3: Force the time to be between 6:00 p.m. and 9:00 p.m., and simulate a partial charge on the tank. Simulate a cooling load by setting the indoor temperature setpoint lower than the ambient temperature. Verify that the TES system starts discharging. This shall be checked by observing tank inlet and outlet temperatures and system flow, or directly by reading an inventory meter where the system has one. Where the system has no charge, verify that the system will still attempt to meet the load through storage.

Step 4: Force the time to be between noon and 6:00 p.m., and simulate a cooling load by lowering the indoor air temperature setpoint below the ambient temperature. Verify that the tank starts discharging and the compressor is off.

Step 5: Force the time to be between 9:00 a.m. to noon, and simulate a cooling load by lowering the indoor air temperature setpoint below the ambient temperature. Verify that the tank does not discharge and the cooling load is met by the compressor.

Step 6: Force the time to be between 9:00 p.m. and 9:00 a.m. and simulate a full tank charge. This can be done in a couple of ways:

(1) By changing the inventory sensor limit that indicates tank capacity to the energy management system so that it indicates a full tank.

(2) By resetting the coolant temperature that indicates a full charge to a higher temperature than the current tank leaving temperature. Verify that the tank charging is stopped.

Step 7: Force the time to be between noon and 6:00 p.m. and simulate no cooling load by setting the indoor temperature setpoint above the ambient temperature. Verify that the tank does not discharge and the compressor is off.

E 805.15.2 Acceptance Criteria. Thermal energy storage (TES) system acceptance criteria shall be as follows:

(1) Verify that the system is able to charge the storage tank during off-peak periods where there is no cooling load.

(2) Verify that tank discharges during on-peak cooling periods.

(3) Verify that the compressor does not run and the tank does not discharge where there is no cooling demand during on-peak periods.

(4) Verify that the system does not operate during a morning shoulder period where there is no cooling demand.

(5) Verify that the system operates in direct mode (with compressor running) during the morning shoulder time period.

E 806.0 Certificate of Acceptance Forms.

E 806.1 General. This section includes the certificate of acceptance forms referenced in Section E 804.0.

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APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the

builder provides to the building owner at occupancy.

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APPENDIX E

Verify measured outside airflow reading is within ± 10% of the total required outside airflow value found in Section E 805.1 Intent: through Section E 805.2.2

Construction Inspection

1. Instrumentation to perform test includes, but not limited to:

a. Watch.

b. Calibrated means to measure airflow.

2. Check one of the following:

Variable Air Volume (VAV) - Check as appropriate:

a. Sensor used to control outdoor air flow must have calibration certificate or be field calibrated.

Calibration certificate (attach calibration certification).

Field calibration (attach results).

Constant Air Volume (CAV) - Check as appropriate:

System is designed to provide a fixed minimum OSA when the unit is on.

For SI units: 1 cubic foot per minute = 0.00047 m [3] /s

Outdoor Air Acceptance

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APPENDIX E

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APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

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APPENDIX E

Verify the individual components of a constant volume, single-zone, unitary air conditioner and heat pump system func- Intent: tion correctly, including: thermostat installation and programming, supply fan, heating, cooling, and damper operation.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to:

a. None required

2. Installation

Thermostat is located within the space-conditioning zone that is served by the HVAC system.

3. Programming (check all of the following):

Thermostat meets the temperature adjustment and dead band requirements.

Occupied, unoccupied, and holiday schedules have been programmed per the facility’s schedule.

Preoccupancy purge has been programmed to meet the requirements of Section E 805.3 through Section E 805.3.2.

A. Functional Testing Requirements. Operating Modes

A. Functional Testing Requirements. Operating Modes Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition

A. Functional Testing Requirements. Operating Modes No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during unoccupied condition
Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|

A. Functional Testing Requirements. Operating Modes

A. Functional Testing Requirements. Operating Modes No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Cooling load during occupied condition
Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|

A. Functional Testing Requirements. Operating Modes

A. Functional Testing Requirements. Operating Modes Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|Manual override
No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|

A. Functional Testing Requirements. Operating Modes

A. Functional Testing Requirements. Operating Modes No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|No-load during unoccupied condition
Heating load during unoccupied condition
No-load during occupied condition
Heating load during occupied condition|

A. Functional Testing Requirements. Operating Modes

A. Functional Testing Requirements. Operating Modes Heating load during occupied condition|

A. Functional Testing Requirements. Operating Modes

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

498 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Intent:

New single zone supply ductwork must be less than 6% leakage rate per Section E 805.4 through Section E 805.4.2, existing single zone ductwork must be less than 15% leakage or other compliance path per Section E 805.4 through Section E 805.4.2.

Construction Inspection

1. Scope of test – New Buildings – this test required on New Buildings only if all check boxes 1(a) through 1(c) are checked.

Existing Buildings – this test required if 1(a) through 1(d) are checked. Ductwork conforms to the following (note if any of these are not checked, then this test is not required): 1(a) Connected to a constant volume, single zone air conditioners, heat pumps, or furnaces.

1(b) Serves less than 5000 square feet of floor area.

1(c) Has more than 25% duct surface area located in one or more of the following spaces.

– Outdoors. – A space directly under a roof where the U-factor of the roof is greater than U-factor of the ceiling. – A space directly under a roof with fixed vents or openings to the outside or unconditioned spaces. – An unconditioned crawl space. – Other unconditioned spaces.

1(d) A duct is extended or any of the following replaced: air handler, outdoor condensing unit of a split system, cooling or heating coil, or the furnace heat exchanger. 2. Instrumentation to perform test includes: a. Duct Pressure Test.

3. Material and Installation. Complying new duct systems shall have a checked box for all of the following categories (a) through (g):

a. Choice of drawbands. (check one of the following)

For SI units: 1 square foot = 0.0929 m [2]

500 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Air Distribution System Leakage Diagnostic.
The installing contractor must pressure test every new HVAC systems that meet the requirements of Section E 805.4 through
Section E 805.4.2 and every retrofit to existing HVAC systems that meet the requirements of Section E 805.4 through Section
E 805.4.2.

For SI units: 1000 British thermal units per hour = 0.293 kW, 1 cubic foot per minute = 0.00047 m [3] /s, 1 metric ton = 1000 kg

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

502 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Intent: Verify that airside economizers function properly.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. Handheld temperature probes calibration. Date: (must be within last year). b. Multimeter capable of measuring ohms and milliamps.
2. Test method (check one of the following): Economizer comes from HVAC system manufacturer installed by and has been factory calibrated and tested. Attach documentation and complete certification statement. No functional testing required.

Economizer field installed and field tested or factory installed and field tested.

3. Installation (check all of the following first level boxes). Economizer lockout setpoint complies with Section E 805.5 through Section E 805.5.2.

Economizer lockout control sensor is located to prevent false readings.

System is designed to provide up to 100% outside air without over-pressurizing the building.

For systems with DDC controls lockout sensor(s) are either factory calibrated or field calibrated.

For systems with non-DDC controls, manufacturer’s startup and testing procedures have been applied.

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

504 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Verify that systems required to employ demand controlled ventilation can vary outside ventilation flow rates based on Intent: maintaining interior carbon dioxide (CO 2 ) concentration setpoints.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. Calibrated handheld CO 2 analyzer. b. Manufacturer’s calibration kit. c. Calibrated CO 2 /air mixtures.
2. Installation. The sensor is located in the high density space between 3 feet and 6 feet above the floor or at the anticipated level of the occupants heads.
3. Documentation of all carbon dioxide control sensors includes (check one of the following): a. Calibration method. Factory-calibration certificate (certificate must be attached). Field calibrated. b. Sensor accuracy. Certified by manufacturer to be no more than +/- 75 ppm calibration certificate must be attached.

nd 6 feet above the floor or at the anticipated level of the occupants heads. 3. Documentation of all carbon dioxide control sensors includes (check one of the following): a. Calibration method. Factory-calibration certificate (certificate must be attached). Field calibrated. b. Sensor accuracy. Certified by manufacturer to be no more than +/- 75 ppm calibration certificate must be attached.

For SI units: 1 inch = 25.4 mm

506 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder provides to

the building owner at occupancy.

508 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Intent: Verify that the supply fan in a variable air volume application modulates to meet system airflow demand.

Construction Inspection

1 Instrumentation to perform test includes, but not limited to: a. Calibrated differential pressure gauge. 2 Installation. Discharge static pressure sensors are either factory calibrated or field-calibrated.

The static pressure location, setpoint, and reset control meets the requirements of Section E 805.7 through Section E 805.7.2.

3 Documentation of all discharge static pressure sensors including (check one of the following): Field-calibrated.

Calibration complete, all pressure sensors within 10% of calibrated reference sensor.

C. PASS / FAIL Evaluation (check one):

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

510 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Ensure that control valves serving variable flow systems are designed to withstand the pump pressure over the full range Intent: of operation.

Construction Inspection

1 Instrumentation to perform test includes, but not limited to: a. Calibrated differential pressure gauge. b. Pump curve submittals showing the shutoff head. 2 Installation. Valve and piping arrangements were installed per the design drawings.

C. PASS / FAIL Evaluation (check one):

For SI units: 1 inch water column = 0.249 kPa

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

512 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Ensure that both the chilled water and hot water supply temperatures are automatically reset based on either building Intent: loads or outdoor air temperature, as indicated in the control sequences.

Construction Inspection

1 Instrumentation to perform test includes, but not limited to: a. Calibrated reference temperature sensor or drywell bath. 2 Installation Supply water temperature sensors have been either factory or field calibrated.

3 Documentation of hydronic system supply temperature sensors including (check one of the following):

Field-calibrated

Calibration complete, hydronic system supply temperature sensors within 1% of calibrated reference sensor or drywell bath.

C. PASS / FAIL Evaluation (check one):

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

514 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Ensure that when loads within the building fluctuate, control valves modulate the amount of water passing through each Intent: coil and add or remove the desired amount of energy from the air stream to satisfy the load.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. Calibrated differential pressure gauge.
2. Installation Pressure sensors are either factory calibrated or field-calibrated.

Pressure sensor location, setpoint, and reset control meets the requirements of Section E 805.10 through Section E 805.10.2.

3. Documentation of all control pressure sensors including (check one of the following): a. Factory-calibrated (proof required). Factory-calibration certificate.

b. Field-calibrated. Calibration complete, all pressure sensors within 10% of calibrated reference sensor.

For SI units: 1 inch water column = 0.249 kPa

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

C. PASS / FAIL Evaluation (check one):

516 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Intent: Ensure that the central demand shed sequences have been properly programmed into the DDC system.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. None.

2. Installation.

The EMCS front end interface enables activation of the central demand shed controls.

C. PASS / FAIL Evaluation (check one):

518 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

The purpose of this test is to verify proper fault detection and reporting for automated fault detection and Intent: diagnostics systems for packaged units.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. List of instrumentation may be needed or included.
2. Installation.

Verify that FDD hardware is installed on equipment by the manufacturer and that equipment make and model include factory-installed FDD hardware that matches the information indicated on copies of the manufacturer’s cut sheets and on the plans and specifications.

For SI units: °C = (°F-32)/1.8

520 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

522 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Intent: Verify that the system detects common faults in air handling units and zone terminal units.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. No instrumentation is required – changes are implemented at the building automation system control station.
2. Installation.

a. The functional testing verifies proper installation of the controls for FDD for air handling units and zone terminal units. No additional installation checks are required.

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

524 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

526 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

Intent: Verify that the system detects common faults in air handling units and zone terminal units.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. No special instrumentation is required to perform these tests.
2. Installation.

Prior to Performance Testing, verify and document the following: The water tank is filled to the proper level.

The water tank is sitting on a foundation with adequate structural strength.

The water tank is insulated and the top cover is in place.

The DES/DXAC is installed correctly (refrigerant piping, etc.).

Verify that the correct model number is installed and configured.

For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per hour = 0.293 kW

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

528 2025 CALIFORNIA MECHANICAL CODE

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APPENDIX E

FIELD TECHNICIAN’S DECLARATION STATEMENT

• I certify under penalty of perjury the information provided on this form is true and correct.

• I am the person who performed the acceptance requirements verification reported on this Certificate of Acceptance (Field Technician).

RESPONSIBLE PERSON’S DECLARATION STATEMENT

• I certify under penalty of perjury that I am the Field Technician, or the Field Technician is acting on my behalf as my employee or my agent and I have reviewed the information provided on this form.

• I am a licensed contractor or registered design professional who is eligible per the requirements of the Authority Having Jurisdiction to take responsibility for the scope of work specified on this document and attest to the declarations in this statement (responsible person).

• I certify that the information provided on this form substantiates that the construction/installation identified on this form complies with the acceptance requirements indicated in the plans and specifications approved by the enforcement agency, and conforms to the applicable acceptance requirements and procedures specified in Section E 801.0 through Section E 806.0.

• I have confirmed that the Installation Certificate(s) for the construction/installation identified on this form has been completed and is posted or made available with the permit(s) issued for the building.

• I will ensure that a completed, signed copy of this Certificate of Acceptance shall be posted, or made available with the building permit(s) issued for the building, and made available to the enforcement agency for all applicable inspections. I understand that a signed copy of this Certificate of Acceptance is required to be included with the documentation the builder

provides to the building owner at occupancy.

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APPENDIX E

Intent: Verify proper operation of distributed energy storage DX systems.

Construction Inspection

1. Instrumentation to perform test includes, but not limited to: a. No special instrumentation is required for the acceptance tests.

For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per hour = 0.293 kW

530 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

APPENDIX E

C. PASS / FAIL Evaluation (check one):

For SI units: 1 metric ton = 1000 kg, 1000 British thermal units per hour = 0.293 kW

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

532 2025 CALIFORNIA MECHANICAL CODE

), Copyright © 2025 IAPMO, and may not be used for any other purpose or distributed to any other persons or parties.

CALIFORNIA MECHANICAL CODE – MATRIX ADOPTION TABLE