TL;DR
EER2 is the federal cooling-efficiency metric that rates an air conditioner or heat pump's output per watt at a steady 95-degree outdoor test, under the M1 test procedure that took effect in 2023 with higher, more realistic external static pressure than the old EER. Because it reflects peak-heat performance rather than a seasonal average, utilities in hot climates and some rebate programs set minimums for it alongside SEER2.
What it means
EER2 is the federal cooling-efficiency metric that rates an air conditioner or heat pump's output per watt at a steady 95-degree outdoor test, under the M1 test procedure that took effect in 2023 with higher, more realistic external static pressure than the old EER. Because it reflects peak-heat performance rather than a seasonal average, utilities in hot climates and some rebate programs set minimums for it alongside SEER2. The number appears on the unit's yellow EnergyGuide label and AHRI certificate.
Where it sits in the glossary
EER2 is part of the Certifications group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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