What each metric is for
ENERGY STAR defines SEER2 as a seasonal cooling-efficiency metric based on heat removed during the cooling season divided by electrical energy consumed during that season. source ↗
ENERGY STAR defines HSPF2 as a seasonal heating-efficiency metric for heat pumps, so it should not be treated as a cooling-only number. source ↗
ENERGY STAR defines EER2 as an efficiency metric at a specific cooling test condition, which makes it useful for comparing performance under a defined load rather than across an entire season. source ↗
How to verify the number
The ENERGY STAR certified mini-split dataset is a product-level source for qualified mini-split and multi-split air conditioners, so it is a better citation than a marketplace badge pasted into a product title. source ↗
AHRI describes its directory as the trusted source for certified HVACR equipment performance, and its air-source heat-pump search is the place to verify rated combinations rather than assuming every indoor and outdoor pairing has the same rating. source ↗ source ↗