Domestic hot water systems, efficiency, controls and installation requirements

Grounded in the retrieved California Energy Code — click a citation to read the verbatim passage:

• § 110.3 High relevance — show source text

  SECTION 110.3—MANDATORY REQUIREMENTS FOR SERVICE WATER-HEATING SYSTEMS AND EQUIPMENT

  (a) Certification by manufacturers. Any service water- heating system or equipment may be installed only if the manufacturer has certified that the system or equipment complies with all of the requirements of this subsection for that system or equipment.

  1. Temperature controls for service water-heating systems. Service water-heating systems shall be equipped with automatic temperature controls capable of adjustment from the lowest to the highest acceptable temperature settings for the intended use as listed in Table 3, Chapter 50 of the ASHRAE Handbook, HVAC Applications Volume or Table 613.1 of the Cali- fornia Plumbing Code for healthcare facilities. Exception to Section 110.3(a)1: Residential occupancies.

  (b) Efficiency. Equipment shall meet the applicable requirements of the Appliance Efficiency Regulations as required by Section 110.1, subject to the following:

  1. If more than one standard is listed in the Appliance Efficiency Regulations, the equipment shall meet all the standards listed; and

  2. If more than one test method is listed in the Appliance Efficiency Regulations, the equipment shall comply with the applicable standard when tested with each test method; and

  3. Where equipment can serve more than one function, such as both heating and cooling, or both space heating and water heating, it shall comply with all the requirements applicable to each function; and

  4. Where a requirement is for equipment rated at its “maximum rated capacity” or “minimum rated capacity,” the capacity shall be as provided for and allowed by the controls, during steady-state operation.

  (c) Installation. Any service water-heating system or equipment may be installed only if the system or equipment complies with all of the applicable requirements of this subsection for the system or equipment.

  1. Outlet temperature controls. On systems that have a total capacity greater than 167,000 Btu/hr, outlets that require higher than service water temperatures as listed in the ASHRAE Handbook, Applications Volume, shall have separate remote heaters, heat exchangers or boosters to supply the outlet with the higher temperature. Exception to Section 110.3(c)1: Systems covered by California Plumbing Code Section 613.0 shall instead follow the requirements of that section.
  2. Controls for hot water distribution systems. Service hot water systems with circulating pumps or with electrical heat trace systems shall be capable of automatically turning off the system. Exception to Section 110.3(c)2: Systems serving healthcare facilities.
  3. Insulation. Unfired service water heater storage tanks and backup tanks for solar water-heating systems shall have: A. External insulation with an installed R -value of at least R-3.5; or

  B. Internal and external insulation with a combined R -value of at least R-16; or

  C. The heat loss of the tank surface based on an 80°F water-air temperature difference shall be less than 6.5 Btu per hour per square foot. 4. Water heating recirculation loops serving multiple dwelling units, high-rise residential, hotel/motel, and nonresiden- tial occupancies. A water heating recirculation loop is a type of hot water distribution system that reduces the time needed to deliver hot water to fixtures that are distant from the water heater, boiler or other water heating equipment. The recirculation loop is comprised of a supply portion, connected to branches that serve multiple dwelling units, guest rooms, or fixtures and a return portion that completes the loop back to the water heating equipment.

• § 110.2 High relevance — show source text

  Units that only have capabilities for partial heat recovery shall meet the requirements of Table 110.2-D, Water
  Chilling Packages—Minimum Efficiency Requirements.
  g. For heat recovery heating chilling package applications where there is simultaneous cooling and heating, compliance with the heating performance heat recover COPHR is
  only required at one of the four heating AHRI 550/590 (I-P) standard ratings conditions of Low, Medium, Hot-Water 1 or Hot-Water 2. Compliance with the cooling-only perfor-
  mance is required as defined in Notes b and c of Table 110.2-I.
  h. Water-to-water heat pumps with a capacity less than 135,000 Btu/h are included in Table 110.2-B, Heat Pumps—Minimum Efficiency Requirements.
  i. Source leaving liquid temperature.
  1. The cooling evaporator liquid flow rate used for the heating rating for a reverse cycle air-to-water heat pump shall be the flow rate determined during the full-load cool-
  ing rating.
  2. The cooling evaporator liquid flow rate for the simultaneous cooling and heating and heat recovery liquid cooled chilling packages rating shall be the liquid flow rates
  from the cooling operation full-load rating.
  3. For heating-only fluid-to-fluid chiller packages, the evaporator flow rate obtained with an entering liquid temperature of 54°F and a leaving liquid temperature of 44°F
  shall be used.
  j. NA means the requirements are not applicable.|

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  ALL OCCUPANCIES—MANDATORY REQUIREMENTS FOR THE MANUFACTURE, CONSTRUCTION AND INSTALLATION OF SYSTEMS, EQUIPMENT AND BUILDING COMPONENTS

  SECTION 110.3—MANDATORY REQUIREMENTS FOR SERVICE WATER-HEATING SYSTEMS AND EQUIPMENT

  (a) Certification by manufacturers. Any service water- heating system or equipment may be installed only if the manufacturer has certified that the system or equipment complies with all of the requirements of this subsection for that system or equipment.

  1. Temperature controls for service water-heating systems. Service water-heating systems shall be equipped with automatic temperature controls capable of adjustment from the lowest to the highest acceptable temperature settings for the intended use as listed in Table 3, Chapter 50 of the ASHRAE Handbook, HVAC Applications Volume or Table 613.1 of the Cali- fornia Plumbing Code for healthcare facilities. Exception to Section 110.3(a)1: Residential occupancies.

  (b) Efficiency. Equipment shall meet the applicable requirements of the Appliance Efficiency Regulations as required by Section 110.1, subject to the following:

  1. If more than one standard is listed in the Appliance Efficiency Regulations, the equipment shall meet all the standards listed; and

  2. If more than one test method is listed in the Appliance Efficiency Regulations, the equipment shall comply with the applicable standard when tested with each test method; and

  3. Where equipment can serve more than one function, such as both heating and cooling, or both space heating and water heating, it shall comply with all the requirements applicable to each function; and

  4. Where a requirement is for equipment rated at its “maximum rated capacity” or “minimum rated capacity,” the capacity shall be as provided for and allowed by the controls, during steady-state operation.

  (c) Installation. Any service water-heating system or equipment may be installed only if the system or equipment complies with all of the applicable requirements of this subsection for the system or equipment. 1.

• § 203.1.2 High relevance — show source text

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  APPENDIX A4 — RESIDENTIAL VOLUNTARY MEASURES

  A4.203.1.2 Prerequisite options. In addition, a minimum of TWO of the efficiency measures specified in Sections A4.203.1.2.1 through A4.203.1.2.7 must be met.

  A4.203.1.2.1 Roof deck insulation, or ducts in conditioned space. Meet one of the three options for the location of ducts and air handlers as well as insulation R -values and installation of a radiant barrier as specified in Title 24, Part 6, Section 150.1(c)9A or B:

  1. Below roof deck insulation with a minimum R -value of 19; or,

  2. Continuous above deck insulation with a minimum R-8 and with an air space present between the roofing and the roof deck; or,

  3. All ducts and air handlers in conditioned space as specified in the Title 24, Part 6, Reference Appendix RA3.1.

  A4.203.1.2.2 High performance walls. Meet the climate zone dependent U -factor or insulation R -value for either 2x6 or 2x4 framing as specified in Title 24, Part 6, Section 150.1(c)1B: maximum U -factor of 0.048.

  A4.203.1.2.3 Compact hot water distribution system. Meet the requirements for installation of Compact Hot Water Distribution Systems specified in the Title 24, Part 6, Reference Appendix RA3.6.5.

  A4.203.1.2.4 Drain water heat recovery. Meet the requirements for installation of Drain Water Heat Recovery specified in Title 24, Part 6, Reference Appendix RA4.4.21.

  A4.203.1.2.5 High performance vertical fenestration. Meet the climate zone dependent U -factor and Solar Heat Gain Coefficient (SHGC) as rated in accordance with Title 24, Part 6, Section 110.6, and shall have a maximum U -factor of 0.21 in Climate Zones 1 − 16, maximum SHGC of 0.23 in Climate Zones 2, 4, and 6 − 14, and maximum SHGC of 0.20 in Climate Zone 15.

  Exception to A4.203.1.2.5: Fenestration in Climate Zones 1, 3, 5, and 16 is not required to comply with the maximum SHGC requirements.

  A4.203.1.2.6 Heat pump water heater demand management. For buildings with heat pump water heating, meet the requirements for installation of controls specified by Title 24, Part 6, Reference Appendix JA13.3.3.

  A4.203.1.2.7 Battery storage system controls. For buildings with battery storage systems, meet the requirements for installation of controls specified by Title 24, Part 6, Reference Appendix JA12 for either the Time-of-Use Control or Advanced Demand Flexibility Control option.

• § 170.1. High relevance — show source text

  000|≥10,000|≥5,000|≥5,000|≥2,000|≥2,000|≥2,000|≥2,000|≥2,000| |≥60% and <70%|≥2,000|≥2,000|≥6,000|≥6,000|≥6,000|NR|NR|≥18,000|≥9,000|≥4,000|≥4,000|≥2,000|≥2,000|≥2,000|≥2,000|≥2,000| |≥70% and <80%|≥2,000|≥2,000|≥6,000|≥5,000|≥5,000|NR|NR|≥15,000|≥8,000|≥3,000|≥3,000|≥2,000|≥2,000|≥2,000|≥2,000|≥2,000| |≥80%|≥2,000|≥2,000|≥6,000|≥5,000|≥5,000|NR|NR|≥12,000|≥7,000|≥3,000|≥3,000|≥2,000|≥2,000|≥2,000|≥2,000|≥2,000|

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  MULTIFAMILY BUILDINGS—PERFORMANCE AND PRESCRIPTIVE COMPLIANCE APPROACHES

  (d) Domestic hot water systems. Water-heating systems shall meet the applicable requirements of 1 or 2 below:

  1. Individual systems. For systems serving individual dwelling units, the water-heating system shall meet the requirement of either A or B, or shall meet the performance compliance requirements of Section 170.1. For recirculation distribution systems serving individual dwelling units, only demand recirculation systems with manual on/off control as specified in the Reference Appendix RA4.4.9 shall be used. A. A single 240 volt heat pump water heater. In addition, meet the following: i. A compact hot water distribution system as specified in Reference Appendix RA4.4.6 in Climate Zones 1 and 16; and

  ii. A drain water heat recovery system that is field verified as specified in the Reference Appendix RA3.6.9 in Climate Zone 16.

  B. A single heat pump water heater that meets the requirements of NEEA Advanced Water Heater Specification Tier 3 or higher. In addition, for Climate Zone 16, a drain water heat recovery system that is field verified as specified in Reference Appendix RA3.6.9. Exception 1 to Section 170.2(d)1: Multifamily buildings four habitable stories or greater may install a gas or propane instantaneous water heater with an input of 200,000 Btu per hour or less and no storage tank. Exception 2 to Section 170.2(d)1: A 120V HPWH may be installed in place of a 240V HPWH for new dwelling units with one bedroom or less.

  2. **Central systems.
• § 140.4 High relevance — show source text

  TABLE 140.4-H—DIRECT EXPANSION (DX) UNIT REQUIREMENTS FOR COOLING STAGES AND COMPRESSOR DISPLACEMENT	Col2	Col3
  COOLING CAPACITY	MINIMUM NUMBER OF MECHANICAL COOLING STAGES	MINIMUM COMPRESSOR DISPLACEMENT
  ≥ 65,000 Btu/h and < 240,000 Btu/h	3 stages	≤ 35% full load
  ≥ 240,000 Btu/h	4 stages	≤ 25% full load

  3. Systems that include a water economizer to meet Section 140.4(e)1 shall include the following: A. Maximum pressure drop. Precooling coils and water-to-water heat exchangers used as part of a water economizer shall either have a waterside pressure drop of less than 15 feet of water, or a secondary loop shall be installed so that the coil or heat exchanger pressure drop is not contributing to pressure drop when the system is in the normal cooling (non-economizer) mode. B. Economizer systems shall be integrated with the mechanical cooling system so that they are capable of providing partial cooling even when additional mechanical cooling is required to meet the remainder of the cooling load. Controls shall not false load the mechanical cooling system by limiting or disabling the economizer or by any other means, such as hot gas bypass, except at the lowest stage of mechanical cooling.

  (f) Supply air temperature reset controls. Space-conditioning systems supplying heated or cooled air to multiple zones shall include controls that automatically reset supply air temperatures. Air distribution systems serving zones that are likely to have constant loads shall be designed for the air flows resulting from the fully reset supply air temperature. Supply air temperature reset controls shall be:

  1. In response to representative building loads or to outdoor air temperature; and

  2025 CALIFORNIA ENERGY CODE 123

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  NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE

  COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY

  2. At least 25 percent of the difference between the design supply-air temperature and the design room air temperature.
  3. Configured with control sequences of operation in accordance with ASHRAE Guideline 36.

  Exception 1 to Section 140.4(f): Systems that meet the requirements of Section 140.4(d)1, without using Exception 1 to that section.

  Exception 2 to Section 140.4(f): Where supply-air temperature reset would increase overall building energy use.

  Exception 3 to Section 140.4(f): Systems supplying zones in which specific humidity levels are required to satisfy process loads. Computer rooms or other spaces with only IT equipment may not use this exception.

  Exception 4 to Section 140.4(f): Systems serving healthcare facilities.

  (g) Electric resistance heating. Electric resistance heating systems shall not be used for space heating.

  Exception 1 to Section 140.4(g): Where an electric resistance heating system supplements a heating system in which at least 60 percent of the annual energy requirement is supplied by site-solar or recovered energy.

• § 140.4 High relevance — show source text

  Exception 1 to Section 140.4(k)4: Hydronic systems that use variable flow to reduce pumping energy in accordance with 140.4(k)1.

  Exception 2 to Section 140.4(k)4: Systems serving healthcare facilities. 5. Water-cooled air conditioner and hydronic heat pump systems. Water circulation systems serving water-cooled air conditioners, hydronic heat pumps, or both that have total pump system power exceeding 5 hp shall have flow controls that meet the requirements of Section 140.4(k)6. Each such air conditioner or heat pump shall have a two-position automatic valve interlocked to shut off water flow when the compressor is off.

  6. Variable flow controls.

  A. Variable speed drives. Individual pumps serving variable flow systems and having a motor horsepower exceeding 5 hp shall have controls or devices (such as variable speed control) that will result in pump motor demand of no more than 30 percent of design wattage at 50 percent of design water flow. The pumps shall be controlled as a function of required differential pressure. B. Pressure sensor location and setpoint. i. For systems without direct digital control of individual coils reporting to the central control panel, differential pressure shall be measured at the most remote heat exchanger or the heat exchanger requiring the greatest differential pressure. ii. For systems with direct digital control of individual coils with a central control panel, the static pressure setpoint shall be reset based on the valve requiring the most pressure, and the setpoint shall be no less than 80 percent open. Pressure sensors may be mounted anywhere.

  Exception 1 to Section 140.4(k)6: Heating hot water systems.

  Exception 2 to Section 140.4(k)6: Condenser water systems serving only water-cooled chillers.

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  NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE

  COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY

  7. Hydronic heat pump (WLHP) controls. Hydronic heat pumps connected to a common heat pump water loop with central devices for heat rejection and heat addition shall have controls that are capable of providing a heat pump water supply temperature dead band of at least 20°F between initiation of heat rejection and heat addition by the central devices.

  Exception to Section 140.4(k)7: 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 shall be allowed. 8. High capacity space heating gas boiler systems. In Climate Zones 1 through 6, 9 through 14, and 16, gas hot water boiler systems for space heating with a total system input of at least 1 MMBtu/h but no more than 10 MMBtu/h shall meet all of the following requirements. A. Boiler system efficiency. Gas hot water boilers shall have a minimum thermal efficiency of 90 percent. Systems with multiple boilers can meet this requirement if the space-heating input provided by equipment with thermal efficiencies above and below 90 percent has an input capacity-weighted average thermal efficiency of at least 90 percent. For boilers federally regulated by combustion efficiency, the calculation for the input capacity-weighted average thermal efficiency shall use the combustion efficiency value. B. **Hot water distribution design.

• § 140.4 High relevance — show source text

  2025 CALIFORNIA ENERGY CODE 125

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  NONRESIDENTIAL AND HOTEL/MOTEL OCCUPANCIES—PERFORMANCE AND PRESCRIPTIVE

  COMPLIANCE APPROACHES FOR ACHIEVING ENERGY EFFICIENCY

  7. Hydronic heat pump (WLHP) controls. Hydronic heat pumps connected to a common heat pump water loop with central devices for heat rejection and heat addition shall have controls that are capable of providing a heat pump water supply temperature dead band of at least 20°F between initiation of heat rejection and heat addition by the central devices.

  Exception to Section 140.4(k)7: 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 shall be allowed. 8. High capacity space heating gas boiler systems. In Climate Zones 1 through 6, 9 through 14, and 16, gas hot water boiler systems for space heating with a total system input of at least 1 MMBtu/h but no more than 10 MMBtu/h shall meet all of the following requirements. A. Boiler system efficiency. Gas hot water boilers shall have a minimum thermal efficiency of 90 percent. Systems with multiple boilers can meet this requirement if the space-heating input provided by equipment with thermal efficiencies above and below 90 percent has an input capacity-weighted average thermal efficiency of at least 90 percent. For boilers federally regulated by combustion efficiency, the calculation for the input capacity-weighted average thermal efficiency shall use the combustion efficiency value. B. Hot water distribution design. The hot water distribution system shall be designed to comply with Items i and ii. i. Coils and other heat exchangers shall be selected so that at design conditions the hot water return temperature entering the boilers is 120°F or less. ii. Under all operating conditions, the water temperature entering the boiler is 120°F or less or the flow rate of supply hot water that recirculates directly into the return system, such as by three-way valves or minimum flow bypass controls, shall be no greater than 20 percent of the design flow of the operating boilers. Exception 1 to Section 140.4(k)8: Where 25 percent of the annual space heating requirement is provided by on-site renewable energy, site-recovered energy or heat recovery chillers. Exception 2 to Section 140.4(k)8: Space heating boilers installed in individual dwelling units. Exception 3 to Section 140.4(k)8: Where 50 percent or more of the design heating load is served using perimeter convective heating, radiant ceiling panels or both. Exception 4 to Section 140.4(k)8: Individual gas boilers with input capacity less than 300,000 Btu/h shall not be included in the calculations of the total system input or total system efficiency.

  (l) Reserved.

  (m) Fan control. Each cooling system listed in Table 140.4-I shall be designed to vary the indoor fan airflow as a function of load and shall comply with the following requirements:

  1. DX and chilled water cooling systems that control the capacity of the mechanical cooling directly based on occupied space temperature shall A. Have a minimum of two stages of fan control with no more than 66 percent speed when operating on stage 1; and B. Draw no more than 40 percent of the fan power at full fan speed, when operating at 66 percent speed.
• California Energy Code Medium relevance — show source text

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  ALL OCCUPANCIES—GENERAL PROVISIONS

  DEW POINT TEMPERATURE is the vapor saturation temperature at a specified pressure for a substance undergoing phase change from vapor to liquid.

  DIRECT DIGITAL CONTROL (DDC) is a type of control where controlled and monitored analog or binary data, such as temperature and contact closures, are converted to digital format for manipulation and calculations by a digital computer or microprocessor, then converted back to analog or binary form to control mechanical devices.

  DIRECT-VENT APPLIANCE or “sealed combustion” appliance is an appliance that is constructed and installed so that air from combustion is derived directly from the outdoors and flue gases are discharged to the outdoors.

  DISPLAY PERIMETER is the length of an exterior wall in a Group B; Group F, Division 1; or Group M Occupancy that immediately abuts a public sidewalk, measured at the sidewalk level for each story that abuts a public sidewalk.

  DOMESTIC HOT WATER SYSTEM APPURTENANCE are all elements that are in series in a domestic hot water distribution system, including fittings (elbows, tees, flanges, etc.), pumps, valves (isolation, mixing, balancing, check, etc.), strainers, hose bibs, coil ubends, meters, sensors, heat exchangers and air separators.

  DOMESTIC WATER HEATING SYSTEMS ( see “service water heating”).

  DOOR is an operable opening in the building envelope including swinging and roll-up doors, fire doors, pet doors and access hatches with less than 25 percent glazed area. When that operable opening has 25 percent or more glazed area it is a glazed door. See Fenestration: Glazed Door.

  DOOR AREA is the total rough opening area which includes the door, and when present, the fenestration, and the fenestration frame components in the door frame assembly.

  DRAIN WATER HEAT RECOVERY (DWHR) is a system that recovers heat from effluent in waste piping and uses it to preheat water in a domestic or service water-heating system in order to reduce water-heating energy usage.

  DRY COOLER is a fan-powered heat rejection device that includes a water or glycol circuit connected by a closed circulation loop refrigerant condenser and is air-cooled.

  DUAL-FUEL HEAT PUMP is an electric heat pump with gas furnace supplemental heat that alternates between the two fuel sources.

  DUCT SEALING is a procedure for installing a space-conditioning distribution system that minimizes leakage of air from or to the distribution system. Minimum specifications for installation procedures, materials, diagnostic testing and field verification are contained in the Reference Residential Appendix RA3 and Reference Nonresidential Appendix NA1.

  DUCT SYSTEM is all the ducts, duct fittings, plenums and fans when assembled to form a continuous passageway for the distribution of air.

  DUCT WALL PENETRATIONS are openings to the duct wall made by pipes, holes, conduit, tie rods or wires.

  DUCTED SYSTEM is an air conditioner or heat pump, either a split system or single-packaged unit, that is designed to be permanently installed equipment and delivers conditioned air to an indoor space through a duct.

  DWELLING is a building that contains one or two dwelling units used, intended or designed to be used, rented, leased, let or hired out to be occupied for living purposes.

• § 204.4.1 Medium relevance — show source text

  The owner shall document the Owner’s Project Requirements (OPR). The design team shall develop the Basis of Design (BOD). The CxA shall review these documents for clarity and completeness. The owner and design team shall be responsible for updates to their respective documents, develop and incorporate commissioning requirements into the construction documents and develop and implement a commissioning plan. The CxA shall verify the installation and performance of the systems to be commissioned, verify that training and operation and maintenance documentation have been provided to the owner’s operations staff and complete a commissioning report.

  Commissioning process activities shall be completed for the following energy-related systems, at a minimum:

  1. Heating, ventilating, air conditioning and refrigeration (HVAC&R) systems (mechanical and passive) and associated controls.
  2. Lighting and daylighting controls.
  3. Domestic hot water systems.
  4. Renewable energy systems (wind, solar, etc.).
  5. Building envelope systems.

  A6.204.4.1 Owner’s Project Requirements (OPR). The expectations and requirements of the building shall be documented by the owner and the designer before the design phase of the project begins. This shall be reviewed by the CxA. At a minimum, this documentation shall include the following:

  1. Environmental and sustainability goals.
  2. Energy efficiency goals.
  3. Indoor environmental quality requirements.

  2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A6.1-3

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  APPENDIX A6.1 — VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

  4. Equipment and systems expectations.
  5. Building occupant and O&M personnel expectations.

  A6.204.4.2 Basis of Design (BOD). A written explanation of how the design of the building systems 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. This shall be reviewed by the CxA. At a minimum, the Basis of Design document shall cover the following systems:

  1. Heating, ventilation, air conditioning (HVAC) systems and controls.
  2. Indoor lighting system and controls.
  3. Water heating system.
  4. Renewable energy systems.

  A6.204.4.3 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. This shall be reviewed by the CxA. The Commissioning Plan shall include the following at a minimum:

  1. General project information.
  2. Commissioning goals.
  3. Systems to be commissioned. Plans to test systems and components shall include at a minimum: 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; and 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 Sections A6.204.4.4 through A6.204.4.6 shall be included.

• § 110.1 Medium relevance — show source text

  1(b), 110.1(c), Table 141.0-E, Table 150.2-D Requirements 110.2(a), Table 110.2D120.6(b)1G, Table 120.6-D Standard 110.2(a), Table 110.2-J Efficient Drift Eliminators 110.2(e) Egress 120.1(d), 130.1(a), 130.1(c)1, 6, 7, Table 130.5-B, 140.6(a)3K, 140.6(c)3H, 150.0(s)2, 150.1(c)4E, 160.2(c), 160.5(b)4, 170.2(e)2C, 4B Electric Clothes dryer 150.0(v), 160.9(c) Cooktop 150.0(u), 160.9(b) Demand 110.4(b) Furnace 110.2(d) Power distribution 160.6 Ready building 160.9 Reheat 141.0(a)2, 141.0(b)2C, 141.0(b)3, 180.2, 180.2(b)2B Resistance heating 110.4(a), 120.2(d), 120.6(a)2, 120.6(a)7, 140.4(g), 141.0(b)2C, 160.3(a)2, 170.2(c)4E Resistance space heat 141.0(b)2C, 150.2(b)1G, 180.2(b)2A, 180.2(b)2B Resistance water heater 150.2(b)1H, 180.2(b)3C Vehicle (EV) charger 110.10(b)1A, 110.10(b)1B Electrical Boxes 150.0(k)1, 160.5(a)1E Circuits 130.5(b), 130.5(d), 141.0(b)2P, Q, R, 160.6(b), 180.2(b)4B Energy monitoring 130.5(b), 141.0(b)2P, Q, R, 160.6(b), 180.2(b)4B Feeder 130.5(a), 141.0(b)2P, 160.6(a), 180.2(b)4B Input power 120.6(a)4G, 120.6(a)8H, 120.6(b)5H, 120.10(a), 140.4(c)1, 170.2(c)4A Load 130.2(c), Table 130.5-A, Table 130.5-B, 160.5(c)2, Table 160.6-A, Table 160.6-B Output 150.1(c)14, 170.2(f) Panel 110.9(c), 150.0(n), 160.4(a), 160.9(c) Power distribution system 100.0(b), 110.11, 120.6(h), 130.0, 130.5, 130.0(a), 141.0(a)1, 141.0(a)2, 141.0(b)2C, 141.0(b)2P, Q, R, 160.6(b), 180.1(a), 180.2(b)4 Receptacle 150.

• § 140.3 Medium relevance — show source text

  Table140.3-C, Table 140.3-D, Table 140.3-E, 140.4(b)5, 150.1(c)3, 150.1(c)4, Table 150.1-A, 150.2(b)1A, 150.2(b)1B, Table 150.2-D, 170.2(a)3A, 170.2(a)3B South-facing 140.3(d)1A, 140.3(d)3B, 150.1(c)4D Spandrel panel 120.7(b)6, 141.0(b)1B, 160.1(b)6, 180.2(a)2D

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  INDEX

  120.7(a)3C, 130.1(d), 140.3(a)9C, 140.3(c), 140.4(g), 140.6(c)1D, 140.6(c)2D, 140.6(c)3D, 140.6(c)3H-I, 140.10(a), Table 140.10-A, 141.0(b)2D, Equation 150.0-B, 150.0(q)1, Table 150.0-G, 150.1(c)3, 150.1(c)8, 150.1(c)12, Equation 150.1-C, 150.2(a)1, 160.1(e)1, Equation 160.2-B, 160.2(c)2, Equation 160.2-C, 160.2(c)5D, Table 160.2-G, 160.3(a)2F, 160.3(c)2H, 160.5(b)4D, 170.2(a)3A, 170.2(b), 170.2(e)4A-B, Equation 170.2-C, 170.2(g), Equation 170.2-D, Table 170.2-U, 180.1(a)1A, 180.1(a)2A, 180.1(b)3A Assembly 120.7(c), 141.0(b)1C, 150.1(c)1C, 160.1(c), 170.2(a)5, 180.2(a)3A Display and task 140.6(c)3H Floor-mounted Air Conditioners and Condensing Units Serving Computer Rooms – Minimum Efficiency Requirements Table 110.2-L Insulation 141.0(b)1C, 150.0(d), 150.1(c)1C, Table 150.2-D, 160.1(c), 170.2(a)5, 180.2(a)3 Plan 140.3(c)1, 170.2(b)1 Flow Controls 10-103.1(b)1B, 10-103(c)3B, 120.5(a)6-7, 140.4(k)5-6, 160.3(d)1FG, 170.2(c)4I Flow-based controls 110.2(e) Grid 150.0(o)1G, 150.0(o)1H, 160.2(b)2A, 160.2(b)2A Hood 150.0(o)1G, 150.

• § 203.2 Medium relevance — show source text

  SECTION A6.203—PERFORMANCE APPROACH

  A6.203.2 Energy performance. It is the intent of this code to encourage green buildings to achieve exemplary performance in the area of energy efficiency.

  A6.203.2.1 CALGreen Tier 1. [OSHPD 1] To achieve CALGreen [Tier 1, buildings must comply with the latest edition of “Savings By](http://www.energysoft.com/ep/ 2007SBDHProcedures.pdf) Design, Healthcare Modeling Procedures” found online at http://www.energysoft.com/ep/ 2007SBDHProcedures.pdf.

  A6.203.2.2 CALGreen Tier 2. [OSHPD 1] To achieve CALGreen Tier 2, buildings must exceed the latest edition of “Savings By Design, Healthcare Modeling Procedures” by a minimum of 15 percent.

  SECTION A6.204—PRESCRIPTIVE APPROACH

  A6.204.1 ENERGY STAR equipment and appliances. All equipment and appliances provided by the builder shall be ENERGY STAR labeled if ENERGY STAR is applicable to that equipment or appliance.

  A6.204.4 Commissioning. [OSHPD 1 & 4] Building commissioning shall be included in the design and construction processes of the building project to verify that the building’s energy related systems are installed, calibrated and perform according to the owner’s project requirements, basis of design and construction documents.

  The owner and designer shall designate an individual as the Commissioning Authority (CxA) to lead, review and oversee the completion of the commissioning process activities. The owner shall document the Owner’s Project Requirements (OPR). The design team shall develop the Basis of Design (BOD). The CxA shall review these documents for clarity and completeness. The owner and design team shall be responsible for updates to their respective documents, develop and incorporate commissioning requirements into the construction documents and develop and implement a commissioning plan. The CxA shall verify the installation and performance of the systems to be commissioned, verify that training and operation and maintenance documentation have been provided to the owner’s operations staff and complete a commissioning report.

  Commissioning process activities shall be completed for the following energy-related systems, at a minimum:

  1. Heating, ventilating, air conditioning and refrigeration (HVAC&R) systems (mechanical and passive) and associated controls.
  2. Lighting and daylighting controls.
  3. Domestic hot water systems.
  4. Renewable energy systems (wind, solar, etc.).
  5. Building envelope systems.

  A6.204.4.1 Owner’s Project Requirements (OPR). The expectations and requirements of the building shall be documented by the owner and the designer before the design phase of the project begins. This shall be reviewed by the CxA. At a minimum, this documentation shall include the following:

  1. Environmental and sustainability goals.
  2. Energy efficiency goals.
  3. Indoor environmental quality requirements.

  2025 CALIFORNIA GREEN BUILDING STANDARDS CODE APPENDIX A6.1-3

  on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

  APPENDIX A6.1 — VOLUNTARY STANDARDS FOR HEALTH FACILITIES [OSHPD 1, 2 & 4]

  4. Equipment and systems expectations.
  5. Building occupant and O&M personnel expectations.