HSPF2 — Heating Seasonal Performance Factor v2

Also known as: HSPF2Heating Seasonal Performance Factor

HSPF2 is the standardized measure of a heat pump's heating efficiency over a typical heating season. Higher HSPF2 = more heat output per unit of electricity consumed. The "2" version (effective 2023) replaced the older HSPF metric with revised test conditions.

Compare the certified HSPF2 ratings for the equipment combinations being proposed. Use the AHRI Directory to check the ratings. A heating-efficiency rating does not by itself establish rebate eligibility.

We handle the electrical scope; your HVAC contractor specifies the equipment. HSPF2 appears in efficiency comparisons and older tax-credit material. Section 25C ended for property placed in service after December 31, 2025.