Introduction: SEER vs. SEER2 (What changed?) SEER (Seasonal Energy Efficiency Ratio) measures the cooling efficiency of central air conditioners and heat pumps. In 2023, the industry moved to SEER2, a more realistic test method. Numbers aren’t directly 1-to-1 with legacy SEER, but the rule still holds: higher SEER2 = better cooling efficiency. For heat pump […]