On January 1, 2023, the Department of Energy (DOE) will require new testing procedures for developing efficiency ratings on split system air conditioners. Products that have gone through these updated testing procedures will display SEER2 and EER2 ratings, in addition to the older SEER/EER ratings. The 2023 testing procedures are more stringent and will result in lower efficiency ratings compared to the older ratings. As we transition all our products to these new testing procedures, we'll publish both ratings on our air conditioners category page for better comparison.