SEER2 stands for Seasonal Energy Efficiency Ratio 2. Specifically, SEER2 is the total heat removed from the conditioned space during the annual cooling season. Driven by new M1** Testing, the goal of new SEER2 testing procedures is to better represent external conditions seen in the field.
All regions will increase by the equivalent of one SEER in 2023, which will result in a lower amount of electricity used for the same amount of cooling. The North will see an increase from 13 to 14 SEER, and the South and Southwest will increase from 14 to 15 SEER. Heat pumps will have a national increase from 14 to 15 SEER. It is important to note that the 2023 requirements only apply to new systems, and existing systems will not need to be replaced if they are already installed and still function.
Starting 01/01/2023, the new regulations require units to be 14 SEER in the North. However, old 13 SEER units can still be installed after 01/01/2023 - as long as they were manufactured before 12/31/2022.
Starting 01/01/2023, the new regulations require units to be 15 SEER in the South. The South cannot install 14 SEER equipment after 01/01/2023.
Notice: This information is only a summary of the DOE's direct final rule to the Energy Policy and Conservation Act of 1975. It is for general reference only. For specific compliance requirements and updates, please refer to the actual code language from the Department of Energy or consult legal counsel.
*https://www.eia.gov/todayinenergy/detail.php?id=40232
**The M1 testing procedure is a new method of product testing designed to better reflect current field conditions. During this test, the DOE increases systems' external static pressure from current SEER (0.1 in. of water) to SEER2 (0.5 in. of water).