TL;DR
The coefficient of performance, or COP, is the ratio of useful heat a heat pump moves to the electrical energy it consumes, so a COP of 3 means three units of heat delivered per unit of electricity. Electric resistance heat is always 1.0 by definition, while air-source heat pumps typically run between 2 and 4 depending on outdoor temperature, falling as it gets colder.
What it means
The coefficient of performance, or COP, is the ratio of useful heat a heat pump moves to the electrical energy it consumes, so a COP of 3 means three units of heat delivered per unit of electricity. Electric resistance heat is always 1.0 by definition, while air-source heat pumps typically run between 2 and 4 depending on outdoor temperature, falling as it gets colder. Manufacturers publish COP at standard rating points such as 47°F and 17°F, figures worth checking when comparing equipment for a cold climate.
Where it sits in the glossary
Coefficient of performance is part of the Trade jargon 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
License: CC-BY-4.0 — quote freely with attribution to ProFix Editorial Team / ProFix Directory.