Questions about your rebate?

2023 Air Source Heat Pump Minimum Efficiency Requirements

Frequently Asked Questions

What’s changing?

There are two key changes taking place in 2023:

  1. The Department of Energy has developed a new procedure for testing heat pump efficiency called the M1 testing method. This testing method was designed to better reflect current field conditions and provide more accurate efficiency ratings. Many heat pump manufacturers are currently in the process of having their equipment re-tested and re-rated. As a result of this testing, equipment Seasonal Energy Efficiency Ratio (SEER) ratings will be replaced with SEER2 ratings and Heating Seasonal Performance Factor (HSPF) ratings will be replaced with HSPF2 ratings.
  2. ENERGY STAR® has developed a cold-climate certification that includes a standard for cold-climate performance. The Energize Connecticut Sponsors are updating heat pump minimum efficiency requirements to align with these new standards and ratings.


When do these changes go into effect?

These changes will be effective January 1, 2023.


How will this affect my installation?

To ease the transition to the new standards, the Energize CT Sponsors will implement a one-year transition period to the new minimum efficiency requirements. If a heat pump system met the program efficiency requirements in 2022, it will continue to be eligible for rebates for equipment installed through December 31, 2023. A complete list of units eligible for residential rebates can be found at