Every heat pump comes with a set of efficiency numbers, and they are easier to read than they look. All of them answer the same question: how much heating or cooling do you get out of the machine for the electricity you put into it? A higher number means more comfort for the same money. There are three of them, plus one that the ratings do not cover and that matters more here than any of them.
The heating number: COP. This is the one to start with. A COP of 3 means the unit delivers three times as much heat as the electricity it uses. Compare that with baseboards, which give you exactly one unit of heat for one unit of electricity and never more, and you have the whole reason a heat pump is cheaper to run. Higher is better.
The cooling numbers: EER and SEER2. These two do the same job for summer. EER measures cooling on one standard hot day, so it is handy for putting two units side by side. SEER2 averages a whole cooling season, which is closer to what you will actually pay. One thing to watch: SEER2 replaced the older SEER in 2023 under a tougher test, and the same machine scores about 5 to 7% lower on the new scale. So a SEER 16 unit in an old brochure is not better than a SEER2 15 unit today. Check which one you are looking at.
The number that matters most in a Quebec winter. None of the three tells you how the unit behaves at −25 °C, and that is the night you bought it for. Ask instead how much of its heating capacity the manufacturer says it still produces at −25 °C or −30 °C. A great COP is worth little if the machine gives up in January and hands the work back to your baseboards. Our guide to choosing a wall-mounted heat pump goes through how to weigh that.
What we install. We fit central heat pumps and wall-mounted units from Mitsubishi, York, Goodman and Moovair, and geothermal systems from WaterFurnace. Geothermal reaches efficiencies no air-source unit can match, for the simple reason that the ground never gets as cold as the air. Efficient models also qualify for government rebates.
The numbers change with every model and size, so the useful answer for your house comes from measuring it, not from a chart. Talk to one of our specialists and we will tell you which unit gives you the most for what you need. Once it is installed, a few habits keep it at that efficiency.
