SEER2 and HSPF2: how AC and heat pumps are rated
Test procedure in effect; SCORE/SHORE not required yet. Certain enforcement provisions delayed one year (September 9, 2025).
Central AC and heat pump efficiency is currently rated in SEER2 (cooling) and HSPF2 (heating). DOE’s final rule of January 7, 2025 updated the test procedure to the latest industry standard (AHRI 210/240-2024), mandatory for testing from July 7, 2025, and created new SCORE and SHORE metrics that are not required until a future standard is based on them.
What to compare
When comparing quotes, compare SEER2 with SEER2 and HSPF2 with HSPF2. Older SEER and HSPF numbers are on a different test and are not directly comparable.
In 2025 DOE proposed (May 29) and finalized (September 9) a one-year delay of certain enforcement provisions tied to a new controls verification procedure.
What to do now
- Ask every installer for the AHRI certificate number of the matched outdoor unit and coil; it lists the certified SEER2 and HSPF2.
Federal Register documents
- 2025-01-07FR Doc. 2024-30852 · Final rule amending the CAC/HP test procedure (SEER2/HSPF2; new SCORE/SHORE metrics).
- 2025-05-29FR Doc. 2025-09591 · Proposed delay of certain controls-verification enforcement provisions.
- 2025-09-09FR Doc. 2025-17227 · Final rule: one-year delay of those enforcement provisions.
A plain-language summary of public documents, not legal or tax advice. Rules in this area have changed several times since 2024; the dates above are the record. Report a change we missed.