AC to HP Overview
Heat pumps provide both cooling and heating by transferring heat rather than generating it. This makes heating significantly more efficient and better for the environment than AC units for cooling paired with gas furnaces or electric resistance for heating. Under AC to HP reach codes, when an existing AC unit is replaced, the new system must either be a heat pump or an AC unit with additional measures that achieve comparable energy savings.
The policies developed by different jurisdictions vary in terms of details and aspects included. For more complete details, visit the Adopted Ordinances page to review specific measures.
Unlocking Residential Energy Savings
In residential buildings, these policies can offer another effective approach to electrification. Many California homes rely on separate systems for heating and cooling, typically pairing a gas furnace with an electric air conditioner. Replacing the AC with a heat pump eliminates the need for fossil fuel based heating, one of the largest contributors to residential emissions. Because heat pumps operate more efficiently than conventional systems, homeowners benefit from lower energy bills over time.
Numerous jurisdictions—including Alameda, Glendale, Los Altos Hills, Los Gatos, Menlo Park, Moreno Valley, Mountain View, Palo Alto, Portola Valley, Saratoga, and Sunnyvale—have adopted AC to HP requirements for single‑family homes and as of this writing, are awaiting approval from the Building Standards Commission (BSC) and the California Energy Commission (CEC) under the new submittal and approval process set forth by Assembly Bill 130 (AB130).
Expanding Impact in Nonresidential Buildings
Although AB 130 temporarily limits new residential reach code adoption through 2031 unless exceptions are met, nonresidential reach codes remain unencumbered and AC to HP reach codes can apply here, too. Nonresidential buildings—offices, schools, retail spaces, and other facilities—often have larger, centralized heating loads served by large AC units with gas furnaces, making electrification via heat pumps particularly beneficial. Aligning heat pump installation with natural equipment replacement cycles minimizes disruption and cost. Additionally, electrified HVAC systems can integrate more seamlessly with onsite solar panels and battery storage systems, mitigating the potential increase in peak demand and enhancing energy resilience – important benefits as California grapples with more frequent heat waves and grid constraints.
Santa Cruz is the first California jurisdiction to adopt a nonresidential AC to HP reach code (also pending approval from the BSC and CEC at this writing), signaling an interest in extending this policy to the commercial sector. Together, residential and nonresidential ordinances demonstrate increasing market confidence in heat pump technology across the state.
Policy Support & Resources
AC to HP reach codes are supported by a combination of technical work and evolving policy efforts. The Statewide Local Energy Codes program provides a range of resources all designed to ease burdens on local staff by lowering administrative barriers and offering standardized justification.
These include model ordinance language, cost‑effectiveness studies, staff reports, and documentation of adopted ordinances. Resources specific to residential buildings can be found here, while those specific to nonresidential buildings can be found here.
Conclusion
AC to Heat Pump reach codes represent another important approach in the state’s broader decarbonization toolkit: a practical, cost-effective way to reduce emissions, enhance energy performance, and modernize California’s building stock. By focusing on equipment turnover events, they continue to achieve HVAC market transformation over time. For both residential and nonresidential buildings, the policy delivers a triple benefit: emissions reduction, energy savings, and utility bill savings.
