Storage tank and pipe insulation requirements

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

• § 160.4 High relevance — show source text

  Exception to Section 160.4(d)3: Boilers with steady state full-load thermal combustion efficiency 90 percent or higher.

  (e) Pipe insulation

  All piping for multifamily domestic hot water systems shall be insulated and meet the applicable requirements in Items 1 through 3 below:

  1. General requirements. A. The first 8 feet of inlet cold water piping from the storage tanks, including piping between a storage tank and a heat trap, shall be insulated. B. Insulation on the piping and domestic hot water system appurtenances shall be continuous. C. Pipe supports, hangers, and pipe clamps shall be attached on the outside of rigid pipe insulation to prevent thermal bridges. D. All pipe insulation seams shall be sealed. E. Insulation for pipe elbows shall be mitered, preformed, or site fabricated with PVC covers. F. Insulation for tees shall be notched, preformed, or site fabricated with PVC covers.

  G. Extended stem isolation valves shall be installed.

  H. All plumbing appurtenances on hot water piping from a heating source to heating plant, at the heating plant, and distribution supply and return piping shall be insulated to meet the following requirements: i. Where the outer diameter of the appurtenance is less than the outer diameter of the insulated pipe that it is attached to, the appurtenance shall be insulated flush with the insulation surrounding the pipe. ii. Where the outer diameter of the appurtenance is greater than the outer diameter of the insulated pipe that it is attached to, the appurtenance shall be insulated with a minimum thickness of 1 inch. iii. The insulation shall be removable and re-installable to ensure maintenance or replacement services can be completed. iv. Valves shall be fully functional without impediment from the insulation.

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  MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS

  2. Insulation thickness. All piping for multifamily domestic hot water systems shall meet the insulation thickness requirements specified in Table 160.4-A. A. For insulation conductivity in the range shown in Table 160.4-A for the applicable fluid temperature range, the insulation shall have the applicable minimum thickness or R -value shown in Table 160.4-A. B. If the insulation conductivity falls outside the range provided in Table 160.4-A applicable fluid temperature range, the insulation shall meet a minimum R -value as indicated in Table 160.4-A. Or, it can have a thickness determined using Equation 160.4-A.

  (Equation 160.4-A)

  K

  [-] k [-]

  T = PR  1 + ------ PRt  – 1

  |TABLE 160.

• § 6.8 High relevance — show source text

  (b) Solar water-heating systems and collectors shall be certified and rated by the Solar Rating and Certification Corporation (SRCC), the International Association of Plumbing and Mechanical Officials, Research and Testing (IAPMO R&T), or a listing agency that is approved by the Executive Director.

  (c) Instantaneous water heaters with an input rating greater than 6.8 kBTU/hr (2kW) shall meet the requirements of Section 110.3(c)6.

  (d) Commercial boilers

  1. Combustion air positive shut-off shall be provided on all newly installed boilers as follows: A. All boilers with an input capacity of 2.5 MMBtu/h (2,500,000 Btu/h) and above, in which the boiler is designed to operate with a nonpositive vent static pressure. B. All boilers where one stack serves two or more boilers with a total combined input capacity per stack of 2.5 MMBtu/h (2,500,000 Btu/h).
  2. Boiler combustion air fans with motors 10 horsepower or larger shall meet one of the following for newly installed boilers: A. The fan motor shall be driven by a variable speed drive, or B. The fan motor shall include controls that limit the fan motor demand to no more than 30 percent of the total design wattage at 50 percent of design air volume.
  3. Newly installed boilers with an input capacity 5 MMBtu/h (5,000,000 Btu/h) and greater shall maintain excess (stack-gas) oxygen concentrations at less than or equal to 5.0 percent by volume on a dry basis over firing rates of 20 percent to 100 percent. Combustion air volume shall be controlled with respect to firing rate or flue gas oxygen concentration. Use of a common gas and combustion air control linkage or jack shaft is prohibited. Exception to Section 160.4(d)3: Boilers with steady state full-load thermal combustion efficiency 90 percent or higher.

  (e) Pipe insulation

  All piping for multifamily domestic hot water systems shall be insulated and meet the applicable requirements in Items 1 through 3 below:

  1. General requirements. A. The first 8 feet of inlet cold water piping from the storage tanks, including piping between a storage tank and a heat trap, shall be insulated. B. Insulation on the piping and domestic hot water system appurtenances shall be continuous. C. Pipe supports, hangers, and pipe clamps shall be attached on the outside of rigid pipe insulation to prevent thermal bridges. D. All pipe insulation seams shall be sealed. E. Insulation for pipe elbows shall be mitered, preformed, or site fabricated with PVC covers. F. Insulation for tees shall be notched, preformed, or site fabricated with PVC covers.

  G. Extended stem isolation valves shall be installed.

  H. All plumbing appurtenances on hot water piping from a heating source to heating plant, at the heating plant, and distribution supply and return piping shall be insulated to meet the following requirements: i. Where the outer diameter of the appurtenance is less than the outer diameter of the insulated pipe that it is attached to, the appurtenance shall be insulated flush with the insulation surrounding the pipe. ii. Where the outer diameter of the appurtenance is greater than the outer diameter of the insulated pipe that it is attached to, the appurtenance shall be insulated with a minimum thickness of 1 inch. iii. The insulation shall be removable and re-installable to ensure maintenance or replacement services can be completed. iv. Valves shall be fully functional without impediment from the insulation.

• § 25218.5 High relevance — show source text

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

  SECTION 120.3—REQUIREMENTS FOR PIPE INSULATION

  Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.3(a) through 120.3(c).

  (a) General requirements. The piping conditions listed below for space-conditioning, service water-heating, and process heating and process cooling systems piping with fluid normal operating temperatures listed in Table 120.3-A-1 or Table 120.3-A2, and the fluid distribution system, shall have at least the amount of insulation specified in Subsection (c):

  1. Space cooling systems. All refrigerant suction, chilled water, and brine fluid distribution systems.
  2. Space heating systems. All refrigerant suction, steam, steam condensate and hot water fluid distribution systems.
  3. Service water-heating systems. A. Recirculating system piping, including the supply and return piping to the water heater. B. The first 8 feet of hot and cold outlet piping, including piping between a storage tank and a heat trap, for a nonrecirculating storage system.

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  NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS

  C. Pipes that are externally heated. 4. Process heating system piping. All refrigerant, steam, steam condensate and hot water fluid distribution systems for heating a process unrelated to space conditioning or service water heating. 5. Process cooling system piping. All refrigerant suction, chilled water, and brine fluid distribution systems for cooling a process unrelated to space conditioning.

  Insulation conductivity shall be determined in accordance with ASTM C335 at the mean temperature listed in Table 120.3-A1 or Table 120.3-A2, and shall be rounded to the nearest [1] / 100 Btu-inch per hour per square foot per °F. Fluid distribution systems include all elements that are in series with the fluid flow, such as pipes, fittings, pumps, valves, strainers, coil u-bends, and air separators, but not including elements that are not in series with the fluid flow, such as expansion tanks, fill lines, chemical feeders, and drains.

  Exception to Section 120.3(a)2: Heat pump refrigerant vapor line shall be installed with a minimum of 0.5-inch-thick or R-3.0 insulation for nonresidential buildings and 0.75-inch-thick or R-6.0 insulation for residential buildings. No insulation is required on the refrigerant liquid line.

  (b) Insulation protection. Pipe insulation shall be protected from damage due to sunlight, moisture, equipment maintenance and wind. Protection shall, at minimum, include the following:

  1. Pipe insulation exposed to weather shall be protected by a cover suitable for outdoor service. The cover shall be water retardant and provides shielding from solar radiation that can cause degradation of the material. Adhesive tape shall not be used to provide this protection.
• § 1217.8.4 High relevance — show source text

  (2) Plastic tube/cable ties, typically nylon, fastened to anchors such as rebar or wire mesh.

  (3) Staples made of metal or plastic or combination thereof, without sharp edges that would harm tube, fastened to insulation or subfloor.

  (4) Plastic rails with integrated tube holders intended for the specific type of tube.

  (5) Insulation sheets with integrated knobs for holding the specific type of tube and intended for this application.

  (6) Other fasteners recommended by the manufacturer. 1217.8.4 Spacing of Tube Fasteners. The maximum spacing between tube fasteners within a concrete floor shall not exceed the spacing specified by the manufacturer or, in the absence of manufacturer’s specifications, 2.5 feet (762 mm). 1217.9 Joist Systems and Subfloors. Where tubing is installed below a subfloor, the tube spacing shall be in accordance with the system design and joist space limitations.

  Where tubing is installed above or in the subfloor, the tube spacing shall not exceed 12 inches (305 mm) center-tocenter for living areas.

  Where tubing is installed in the joist cavity, the cavity shall be insulated with not less than R-12 material below the heated space.

  An air space of not less than 1 inch (25.4 mm) and not more than 3 inches (76 mm) shall be maintained between the top of the insulation and the underside of the floor unless a conductive plate is installed in accordance with manufacturer’s instructions.

  Where tubing is installed in panels above or in the subfloor and not embedded in concrete, the floor assembly shall be insulated with not less than R-5 material below the tubing when installed over habitable space.

  1217.9.1 Tubing Fasteners. Tubing that is installed within joist spaces and subfloor panel systems shall be fastened according to manufacturer’s instructions. Unless prohibited by the manufacturer, tubing fasteners shall include the following:

  (1) Heat transfer panel systems made of wood, aluminum or other thermally conductive materials intended for this application and the specific type of tube.

  (2) Staples made of metal or plastic or combination thereof, without sharp edges that would harm tube. intended for this application and the specific type of tube fastened to subfloor.

  (3) Plastic rails with integrated tube holders intended for the specific type of tube.

  (4) Other fasteners recommended by the manufacturer. 1217.10 Wall and Ceiling Panels. Where radiant tubing is installed in the stud wall cavity or the ceiling joist cavity, the cavity shall be insulated with not less than R-12 material. The insulation shall be installed in such a manner as to prevent heating or cooling loss from the space intended to be controlled.

  An air space of not less than 1 inch (25.4 mm) and not more than 3 inches (76 mm) shall be maintained between the insulation and the interior surface of the panel unless a conductive plate is installed.

  1217.10.1 California Energy Code Pipe Insulation Requirements. See California Energy Code Sections 150.0(j)2 and 120.3(c) for pipe insulation requirements based on fluid temperature and pipe diameter – where California Energy Code Table 120.3-A-1 or Table 120.3- A-2 specifies insulation greater than R- 12, the higher value is required.

• § 87.9 High relevance — show source text

  9 kW) and larger| |Additions or
  Alterations|Zone terminal unit such as VAV box|Where existing zones served by the same air handling,
  chilled water, or hot water systems that have DDC| |Additions or
  Alterations|Air handling system or fan coil|Where existing air handling system(s) and fan coil(s)
  served by the same chilled or hot water plant have DDC| |Additions or
  Alterations|New air handling system and all
  new zones served by the system|Individual systems with design heating or cooling capacity of
  300 kBtu/h and larger and supplying more than three zones and
  more than 75 percent of zones are new| |Additions or
  Alterations|New or upgraded chilled water plant|Where all chillers are new and plant design cooling
  capacity is 300 kBtu/h (87.9 kW) and larger| |Additions or
  Alterations|New or upgraded hot water plant|Where all boilers are new and plant design heating
  capacity is 300 kBtu/h (87.9 kW) and larger|

  (k) Optimum start/stop controls. Space conditioning systems with DDC to the zone level shall have optimum start/stop controls. The control algorithm shall, as a minimum, be a function of the difference between space temperature and occupied setpoint, the outdoor air temperature, and the amount of time prior to scheduled occupancy. Mass radiant floor slab systems shall incorporate floor temperature onto the optimum start algorithm.

  Exception to Section 120.2(k): Systems that must operate continuously.

  (l) HVAC hot water temperature. Zones that use hot water for space heating shall be designed for a hot water supply temperature of no greater than 130°F.

  Note: Authority: Sections 25213, 25218, 25218.5, 25402 and 25402.1, Public Resources Code. Reference: Sections 25007, 25008, 25218.5, 25310, 25402, 25402.1, 25402.4, 25402.8, and 25943, Public Resources Code.

  SECTION 120.3—REQUIREMENTS FOR PIPE INSULATION

  Nonresidential and hotel/motel buildings shall comply with the applicable requirements of Sections 120.3(a) through 120.3(c).

  (a) General requirements. The piping conditions listed below for space-conditioning, service water-heating, and process heating and process cooling systems piping with fluid normal operating temperatures listed in Table 120.3-A-1 or Table 120.3-A2, and the fluid distribution system, shall have at least the amount of insulation specified in Subsection (c):

  1. Space cooling systems. All refrigerant suction, chilled water, and brine fluid distribution systems.
  2. Space heating systems. All refrigerant suction, steam, steam condensate and hot water fluid distribution systems.
  3. Service water-heating systems. A. Recirculating system piping, including the supply and return piping to the water heater. B. The first 8 feet of hot and cold outlet piping, including piping between a storage tank and a heat trap, for a nonrecirculating storage system.

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  NONRESIDENTIAL, HOTEL/MOTEL OCCUPANCIES, AND COVERED PROCESSES—MANDATORY REQUIREMENTS

• § 90.1 Medium relevance — show source text

  [ASHRAE 90.1: TABLE 6.8.3-2]

  FLUID OPERATING TEMPERATURE RANGE (°F) AND USAGE	INSULATION CONDUCTIVITY	Col3	NOMINAL PIPE SIZE OR TUBE SIZE (inches)	Col5	Col6	Col7	Col8
  FLUID OPERATING TEMPERATURE RANGE (°F) AND USAGE	CONDUCTIVITY Btu•inch/(h•f2•°F)	MEAN RATING TEMPERATURE °F	<1	1 to <11_/_2	11_/_2 to <4	4 to <8	≥8
  FLUID OPERATING TEMPERATURE RANGE (°F) AND USAGE	CONDUCTIVITY Btu•inch/(h•f2•°F)	MEAN RATING TEMPERATURE °F	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)	INSULATION THICKNESS (inches)
  40 to 60	021 to 0.27	75	0.5	0.5	1.0	1.0	1.0
  <40	0.20 to 0.26	50	0.5	1.0	1.0	1.0	1.5

  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).

• § 180.2 Medium relevance — show source text

  Existing duct systems constructed, insulated or sealed with asbestos are not required to comply with the requirements of Subsection 180.2(b)2Biiib.

  2025 CALIFORNIA ENERGY CODE 279

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  MULTIFAMILY BUILDINGS—ADDITIONS, ALTERATIONS AND REPAIRS TO EXISTING MULTIFAMILY BUILDINGS

  3. Hot water systems . Altered or replacement water-heating systems or components serving individual dwelling units shall meet the applicable requirements below: A. Pipe insulation. For newly installed piping and existing accessible piping, the insulation requirements of Section 160.4(e) shall be met. B. Distribution system. For recirculation distribution system serving individual dwelling units, only demand recirculation systems with manual on/off control as specified in Reference Appendix RA4.4.9 shall be installed. C. Water-heating system. The water-heating system shall meet one of the following: i. A natural gas or propane water-heating system; or ii. A single heat pump water heater. The storage tank shall not be located outdoors and shall be placed on an incompressible, rigid insulated surface with a minimum thermal resistance of R-10. The water heater shall be installed with a communication interface that either meets the requirements of Section 110.12(a) or has an ANSI/CTA-2045-B communication port; or iii. A single heat pump water heater that meets the requirements of NEEA Advanced Water Heater Specification Tier 3 or higher; or iv. If the existing water heater is an electric resistance water heater, a consumer electric water heater. v. A water-heating system determined by the Executive Director to use no more energy than the one specified in Sections 180.2(b)3Ci through iii above; or if no natural gas is connected to the existing water heater location, a water-heating system determined by the Executive Director to use no more energy than the one specified in Section 180.2(b)3Civ above.

  4. Lighting. A. Dwelling unit lighting. The altered lighting system shall meet the lighting requirements of Section 160.5(a). The altered luminaires shall meet the luminaire efficacy requirements of Section 160.5(a). Where existing screw base sockets are present in ceiling-recessed luminaires, removal of these sockets is not required, provided that new JA8 compliant trim kits or lamps designed for use with recessed downlights or luminaires are installed. B. Common use area—lighting, sign lighting, and electrical power distribution systems . i. Spaces with lighting systems installed for the first time shall meet the applicable requirements of Sections 110.9, 160.5(b)1, 160.5(b)2, 160.5(b)3, 160.5(b)4, 160.5(c), 160.5(e), 170.2(b), and 170.2(e)1 through 170.2(e)6. ii. When the requirements of Section 160.5(b)4D are triggered by the addition of skylights to an existing building and the lighting system is not recircuited, the daylighting control need not meet the multi-level requirements in Section 160.5(b)4D. iii. New internally and externally illuminated signs shall meet the requirements of Sections 110.9, 160.5(d) and 170.2(e)7. iv. Altered indoor lighting systems.

• § 150.0 Medium relevance — show source text

  Pipe insulation. For newly installed and existing accessible piping, the insulation requirements of Section 150.0(j)1 shall be met. ii. Distribution system. 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 installed. iii. Water heating system. The water heating system shall meet one of the following: a. A natural gas or propane water-heating system; or b. A single heat pump water heater. The storage tank shall not be located outdoors and be placed on an incompressible, rigid insulated surface with a minimum thermal resistance of R-10. The water heater shall be installed with a communication interface that either meets the requirements of Section 110.12(a) or has an ANSI/CTA-2045-B communication port; or c. A single heat pump water heater that meets the requirements of NEEA Advanced Water Heater Specification Tier 3 or higher; or d. If the existing water heater is an electric resistance water heater, a consumer electric water heater; or e. A water-heating system determined by the Executive Director to use no more energy than the one specified in Item a above; or if no natural gas is connected to the existing water heater location, a water-heating system determined by the executive director to use no more energy than the one specified in Item d above. I. Roofs. Replacements of the exterior surface of existing roofs, including adding a new surface layer on top of the existing exterior surface, shall meet the requirements of Section 110.8 and the applicable requirements of Subsections i and ii where more than 50 percent of the roof is being replaced. i. Steep-sloped roofs. Steep-sloped roofs shall meet the following: New roofing products in Climate Zones 4 and 8 through 15 shall have a minimum aged solar reflectance of 0.20 and a minimum thermal emittance of 0.75, or a minimum SRI of 16. Exception 1 to Section 150.2(b)1Ii: The following shall be considered equivalent to Subsection i: a. Buildings with ceiling assemblies with a U -factor lower than or equal to 0.025 or that are insulated with at least R-38 ceiling insulation; or b. Buildings with a radiant barrier in the attic, where the radiant barrier is not installed directly above spaced sheathing, meeting the requirements of Section 150.1(c)2; or c. In Climate Zones 2, 4, 9, 10, 12 and 14, buildings that have no ducts in the attic; or d. Buildings with R-2 or greater continuous insulation above or below the roof deck. Exception 2 to Section 150.2(b)1Ii: Roof area covered by building integrated photovoltaic panels or building integrated solar thermal panels is not required to meet minimum requirements for aged solar reflectance, thermal emittance or SRI.

• § 0.34 Medium relevance — show source text

  32–0.34|250|Inches|4.5|5.0|5.0|5.0|5.0| |Above 350|0.32–0.34|250|_R-_value|R-37|R-41|R-37|R-27|R-23| |251–350|0.29–0.32|200|Inches|3.0|4.0|4.5|4.5|4.5| |251–350|0.29–0.32|200|_R-_value|R-24|R-34|R-35|R-26|R-22| |201–250|0.27–0.30|150|Inches|2.5|2.5|2.5|3.0|3.0| |201–250|0.27–0.30|150|_R-_value|R-21|R-20|R-17.5|R-17|R-14.5| |141–200|0.25–0.29|125|Inches|1.5|1.5|2.0|2.0|2.0| |141–200|0.25–0.29|125|_R-_value|R-11.5|R-11|R-14|R-11|R-10| |105–140|0.22–0.28|100|Inches|1.0|1.5|1.5|1.5|1.5| |105–140|0.22–0.28|100|_R-_value|R-7.7|R-12.5|R-11|R-9|R-8| |40–60|0.21–0.27|75|Inches|0.75|0.75|1.0|1.0|1.0| |40–60|0.21–0.27|75|_R-_value|R-6|R-5|R-7|R-6|R-5|

  222 2025 CALIFORNIA ENERGY CODE

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  MULTIFAMILY BUILDINGS—MANDATORY REQUIREMENTS

  TABLE 160.3-D—PIPE INSULATION THICKNESS REQUIRED (thickness in inches or R-value)—continued	Col2	Col3	Col4	Col5	Col6	Col7	Col8	Col9
  FLUID OPERATING TEMPERATURE RANGE (°F)	INSULATION CONDUCTIVITY	INSULATION CONDUCTIVITY		NOMINAL PIPE DIAMETER (in inches)	NOMINAL PIPE DIAMETER (in inches)	NOMINAL PIPE DIAMETER (in inches)	NOMINAL PIPE DIAMETER (in inches)	NOMINAL PIPE DIAMETER (in inches)
  FLUID OPERATING TEMPERATURE RANGE (°F)	Conductivity (in Btu·in/h·ft2· °F)	Mean Rating Temperature (°F)	Mean Rating Temperature (°F)	< 1	1 to < 1.5	**1.

• § 0.24 Medium relevance — show source text

  all piping in electric trace tape systems and the first 8 feet of piping from the storage tank for
  nonrecirculating systems)|Service water-heating systems (recirculating sections, all piping in electric trace tape systems and the first 8 feet of piping from the storage tank for
  nonrecirculating systems)|Service water-heating systems (recirculating sections, all piping in electric trace tape systems and the first 8 feet of piping from the storage tank for
  nonrecirculating systems)|Service water-heating systems (recirculating sections, all piping in electric trace tape systems and the first 8 feet of piping from the storage tank for
  nonrecirculating systems)|Service water-heating systems (recirculating sections, all piping in electric trace tape systems and the first 8 feet of piping from the storage tank for
  nonrecirculating systems)|Service water-heating systems (recirculating sections, all piping in electric trace tape systems and the first 8 feet of piping from the storage tank for
  nonrecirculating systems)|Service water-heating systems (recirculating sections, all piping in electric trace tape systems and the first 8 feet of piping from the storage tank for
  nonrecirculating systems)| |Above 105|0.24-0.28|100|0.5|1.0|1.0|1.5|1.5|1.5| |Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)|Space cooling systems (chilled water, refrigerant and brine)| |40-60|0.23-0.27|75|0.5|0.5|0.5|1.0|1.0|1.0| |Below 40|0.23-0.27|75|1.0|1.0|1.5|1.5|1.5|1.5|

  A6.207.6.1 For insulation with a conductivity in the range shown in Table A6.207.6-A for the applicable fluid temperature range, the insulation shall have the applicable thickness shown in Table A6.207.6-A.

  A6.207.6.2 For insulation with a conductivity outside the range shown in Table A6.207.6-A for the applicable fluid temperature range, the insulation shall have a minimum thickness as calculated with Equation A6.207.6-A below.

  — EQUATION A6.207.6-A INSULATION THICKNESS EQUATION

  K

  [-] k [-]

  T = PR  1 + ------ PRt  – 1

  where:

  T = Minimum insulation thickness for material with conductivity K, inches.

  PR = Pipe actual outside radius, inches.

  t = Insulation thickness from Table A6.207.6-A, inches.

  K = Conductivity of alternate material at the mean rating temperature indicated in Table A6.207.6-A, for the applicable fluid temperature range, in Btu-inch per hour per square foot per °F.

• § 90.1 Medium relevance — show source text

  (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}

  2025 CALIFORNIA MECHANICAL CODE 447

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

  APPENDIX E

  »

  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).

• § 805.14.1.3 Medium relevance — show source text

  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).