Does California Require a Heat Pump When You Replace an AC?
No. For a house under the adopted 2025 Energy Code, replacing an air conditioner does not require a heat pump. Section 150.2(b)1 asks for duct sealing, charge and airflow checks in certain zones and a setback thermostat, and it only bars electric resistance as primary heat. Heat pump rules sit in new homes and some commercial rooftop replacements.
- Choose your report
- Upload your plans
- Pay securely
- Permit-ready report by email
Where that was checked
Section 150.2(b)1 lists items A to N for alterations. Three touch a replaced air conditioner: 1C for entirely new or complete replacement systems, 1F for charge, airflow and thermostat, and 1G for heating fuel. None says an air conditioner must be replaced by a heat pump. The Energy Commission's "What's New for Single-Family Residential" summary (revised 19 February 2025) lists the 2025 HVAC changes, among them the 90-minute defrost timer and the 35 F supplementary-heat lockout, and it names no AC-to-heat-pump rule.
What a replaced house AC must do
- Seal and verify the ducts to 10 percent total or 7 percent to outside, even when only the outdoor unit changes (Section 150.2(b)1E; Example 9-35).
- Verify charge and airflow for air-cooled air conditioners in climate zones 2 and 8 to 15 (150.2(b)1Fii).
- Replace the thermostat with a setback type when refrigerant-containing parts are replaced (150.2(b)1Fi).
Where heat pumps are required
For a newly constructed house, Section 150.1(c)6 asks for a heat pump as the prescriptive heating system, with the performance method as the alternative. Section 150.0 states that its requirements apply to newly constructed buildings and that Section 150.2 decides what reaches alterations. In commercial work, Section 141.0(b)2Cii and Table 141.0-E-1 point new or replacement single-zone rooftop units under 65,000 Btu/h in retail, school, office and library buildings toward a single-zone heat pump, or an air conditioner with a furnace or a dual fuel heat pump, in most climate zones, unless the electrical service cannot carry the load. Commercial scope is quoted per project at rooftop unit replacement.
Local rules can add more
Section 10-106 allows cities to adopt stricter energy standards once the Commission approves them, so ask the building department; the background is on reach codes. Air-district rules are a separate layer, outlined on gas furnace replacement.
If you choose a heat pump anyway, compare it on swapping central AC for a heat pump and the air conditioner checklist. Orders start at residential Title 24.
Common Title 24 Questions
- What is Title 24?
- Do I need a Title 24 report?
- How much does a Title 24 report cost?
- How long does a Title 24 report take?
- What is included in a Title 24 report?
- What plans do I need to upload?
Frequently Asked Questions
None appears in the adopted 2025 Energy Code provisions reviewed for this page. Headlines about proposals are not the adopted text, so confirm with your building department.
Prescriptively yes, under Section 150.1(c)6, unless the project complies through the performance method of Section 150.1(b)1.
Explore Heat Pumps
- What SEER2 Does California Require for a Home AC or Heat Pump?
- Can I Swap My Central AC for a Heat Pump? What Title 24 Adds
- Heat Pump Replacement Title 24 Checklist
- Heat Pump With a Gas Furnace Backup: What Title 24 Requires
- How Big Can a Replacement AC or Heat Pump Be Under Title 24?
View all Heat Pumps guides → · HVAC and Water Heating · Title 24 guide