2025 Single-Family Pools and Spas FAQs

The 2025 Energy Code has requirements for single-family pools and spas when equipment like heating systems and circulation pumps is installed. Sections 110.4(a, b, c, d), Sections 150.0(p)(1A,1D,1E), Sections 150.2(a) (additions), and 150.2(b) (alterations) specify these requirements. 

Section 110.4 applies for residential single-family pools and spas when installing new systems or equipment including primary heating sources such as heat pumps. Requirements address: 

• Heating source sizing in accordance with Reference Appendices, Joint Appendix JA16, 
• Length of pipe between the heater and filter,  
• Directional inlets and time switches, and  
• Covers.  

The requirements also apply for repairs when changing the motor or the heating component in a heater, as well as when altering the entire system with a new heater or circulation pump, see Section 150.2(b)1.  

Section 100.1 defines pools and spas as follows: 

Pools include any structure of product designed for swimming, bathing or wading, designed and manufactured to be connected with a circulation system either in-ground, above-ground and on-ground and wading pools. Pools are not intended to be drained and filled with each use. 

Residential pools are designed to be used as an accessory to a residential environment for use only by members of the household and guests with specification based on American National Standards Institute (ANSI)/ Association of Pool & Spa Professionals (APSP)/ International Code Council (ICC)-4, 2012 (R2022) or American National Standards Institute (ANSI)/ Association of Pool & Spa Professionals (APSP)/ International Code Council (ICC)-5, 2011 (R2022). 

Spa is a vessel containing heated water where humans can immerse themselves and is not a pool or a bathtub.

Section 110.4(a) specifies manufacturer product certification requirements for heaters installed in new or existing pools or spas: 

• Heater efficiency must comply with state or federal appliance efficiency standards, see Section 110.1. 
• On-off switch located or attached to the exterior of the heating equipment, readily accessible, and allows turning off heater with no adjustment to the thermostat setting. 
• Instructions on a weatherproof plate or placard that is permanent, legible, and includes the energy efficiency rating and functional operation of the heating system.  

Section 110.4(b) specifies the testing requirements based on fuel type used to heat water for pools and spas in Table 110.4-A.

Table 110.4-A HEATING EQUIPMENT STANDARDS 

Section 110.4(b) includes the following requirements. 

• On piping, there must be: 
  • A minimum of 18 inches of either horizontal or vertical pipe between the filter and the heating equipment, or  
  • Include dedicated suction and return lines, or  
  • Built-in or built-up connections for addition of solar heating systems in the future. 
  • Outdoor pools and spas with either electric or gas heating systems must have a cover to retain heat and reduce waste of heat and energy. 
• Pools must be equipped with: 
  • Directional inlets for proper pool water mixture with time switches and control mechanisms permanently installed for water circulation.  
  • All pumps must be programmable to operate during off-peak electric demand hours and to minimize pump operation while maintaining water conditions based on public health requirements. 

Section 110.4(c) specifies heater sizing for new pools and spa heaters. Primary heaters must be either a heat pump pool heater or solar thermal heating system or a combination of both. Electric resistance or gas may be used, but only as a supplemental heating source and combined with on-site renewable energy systems. Heating systems or units must meet the following sizing requirements: 

• A solar collector surface area equivalent to at least 60% or more of the single-family residential pool and spa surface. 
• A heat pump pool heater sized based on Reference Joint Appendix JA16.3 with a supplementary heater, if needed, of any energy source. 
• A heating system with at least 60% of its annual heating energy from an on-site renewable energy or on-site recovered energy source. 
• A solar pool heating system and heat pump pool heater combined and no additional supplementary heater. 
• Heating equipment or system considered by the Executive Director not to use more energy than the heating systems listed above. 

Exceptions to Section 110.4(c) are: 

• Portable electric spas that comply with California Code of Regulations, Title 20 § 1605.3(g)(7) of the Appliance Efficiency Regulations. 
• Alterations to existing pools and spas with existing heating equipment. 
• Pool and/or spa heated only with a solar pool heating system and no other backup heater. 
• Heating systems used exclusively for permanent spa applications in existing buildings where gas is available. 
•  Heating systems used exclusively for permanent spa applications in buildings with insufficient Solar Access Roof Area (SARA) for a solar pool heating system installation as required in Section 150.1(c)14. 

Section 110.4(d) specifies the controls requirements for heat pump pool heaters with supplementary heating as follows: 

• Supplemental heating must not operate when the heating load can be met by the heat pump pool heater independently. 
• The heat pump pool heater cut-on temperature is higher than the supplementary heater cut-on temperature. 
• The heat pump pool heater cut-off temperature is higher than the supplementary heater cut-off temperature.  

Section 110.5 specifies that natural gas pool and spa heaters shall not have a continuously burning pilot light. 

Section 150.0(p)1A, 1D, 1E specifies the installation of pool systems and equipment that meet the applicable requirements in Section 110.4, as well as the following:  

• Dedicated-purpose pool pumps and replacement dedicated-purpose pool pump motors must meet state and federal appliance requirements and be listed in the Commission’s directory of certified equipment.  
• Dedicated-purpose pool pump standards are in Title 20, §1605.1(g)(7) of the Appliance Efficiency Regulations. 
• Dedicated-purpose pool pump motor replacement standards are in Title 20, §1605.3 of the Appliance Efficiency Regulations.  
• Pool pump flow rates are specified in Section 150.0(p)1B. 
• Filtration pumps shall be sized or programmed to turn over the pool volume in 6 hours or 36 gallons per minute, whichever rate is greater. 
• Dedicated-purpose pool pumps equipped with more than one speed must have controls that default to: 
  • The filtration flow rate when additional pool loads are absent. 
  • The filtration flow rate within 24 hours after being overridden and have an override control for pool maintenance services. 

Sections 150.0(p)2, (p)3, (p)4 specify applicable requirements in Section 110.4 for the installation of pool systems and equipment, which include pump sizing and flow rate, system piping, filters, and valves: 

• The piping system required before the pump equipment shall include a length of a straight pipe more than or equal to 4 times the pipe diameter.  
• The velocity of water in the pool pipe is sized at the maximum flow for auxiliary pool loads, not to exceed 8 feet/second in the return line and 6 feet/second in the suction line.  
• The piping system shall include sweep elbows or elbow-type with a pressure drop less than the length of 30 pipe diameters of a straight pipe. 
• Filter size must comply with NSF (National Sanitation Foundation)/ANSI (American National Standards Institute) 50 based on the maximum rate of pool water passing through the filter. 
• Backwash valves must be at least 2 inches or the diameter of the return pipe, whichever is larger. 

Yes. Section 110.4(b)3 requires outdoor pools and spas that are equipped with either electric or gas heating equipment to have a cover installed to retain heat and prevent heat loss to reduce waste of energy. 

To demonstrate compliance, the installing contractor should submit the Certificate of Installation:  CEC-CF2R-PLB-03-E document. 

Section 150.0(p)1C specifies the maximum filtration flow rate is the rate needed to turn over the pool volume in 6 hours (or 360 minutes) or 36 gpm, whichever is larger.  

For a 25,000-gallon pool, the maximum filtration rate is 69 gpm by using equation [Max Flow Rate (gpm) = Pool Volume (gallons) / 360 minutes].  

Since Section 150.0(p)1C requires that the maximum filtration flow rate be the larger of 69 gpm and 36 gpm, the maximum filtration flow rate is 69 gpm. The pump is adequately sized, as long as a control is installed to operate the pump on low speed for filtration, 39 gpm.  

Section 150.0(p)2B requires that the maximum flow for auxiliary pools loads is: 

• 8 feet per second in the return piping, 
• 6 feet per second in the suction piping. 

Referencing Table 5-9, these flow rates equate to:  

• 2-inch return piping, and 
• 2.5-inch suction.  

See the Blueprint and Single-Family Compliance Manual for more information, including articles and frequently asked questions about the 2025 Energy Code.