Heat pump spec sheets are full of acronyms, but three numbers do most of the work. HSPF measures seasonal heating efficiency, SEER measures seasonal cooling efficiency, and COP measures efficiency at a single moment and temperature. In most of Canada, heating matters far more than cooling, so focus on HSPF and on the COP and capacity a unit delivers in deep cold. SEER is a secondary check.
Key takeaways
- HSPF = seasonal heating efficiency. Higher is better, and it's the key number for Canadian homes.
- SEER = seasonal cooling efficiency. Useful, but less important where heating dominates.
- COP = heat out divided by electricity in at a specific temperature. A COP of 3 means three units of heat for one unit of electricity.
- Newer "2" ratings (HSPF2, SEER2) use tougher test conditions, so the numbers look lower than older ratings for the same equipment.
- For cold climates, look at low-temperature COP and capacity at -15°C and below, not just headline ratings.
COP: the foundation
Coefficient of performance (COP) is the simplest efficiency measure. It's the heat delivered divided by the electrical energy used, both in the same units.
- Electric baseboards: COP = 1.0
- A typical air-source heat pump at 8°C: COP around 3–4
- The same heat pump at -15°C: COP often around 1.8–2.5
- A ground-source (geothermal) heat pump: COP often 3–5 year-round, because ground temperature stays stable
COP changes with outdoor temperature. As it gets colder, the heat pump works harder to pull heat from the air. That's why a single COP figure means little without the temperature it was measured at. See our geothermal page for why ground-source systems keep such steady COPs.
HSPF: seasonal heating efficiency
Heating Seasonal Performance Factor (HSPF) estimates total heat delivered over a heating season, in BTUs, divided by total electricity used, in watt-hours. It blends performance across a range of temperatures, including defrost cycles and backup heat use.
A handy conversion: seasonal COP ≈ HSPF ÷ 3.412. An HSPF of 10 works out to an average COP of roughly 2.9.
Climate regions matter
HSPF is calculated for a climate region. North American tests define several regions. Region IV represents a moderate U.S. climate, and Region V represents colder conditions like much of Canada. The same heat pump gets a lower HSPF in Region V because it spends more time in cold weather. Canadian efficiency regulations reference the colder region, so compare like with like when reading U.S.-sourced spec sheets.
SEER: seasonal cooling efficiency
Seasonal Energy Efficiency Ratio (SEER) is total cooling over a season divided by electricity used. Typical ranges:
- Older central air conditioners: 10–13
- Current standard equipment: around 14–16
- High-efficiency mini-splits: 20 and up
For most Canadian homes, a high SEER is a bonus rather than a deciding factor. In hotter parts of southern Ontario, the B.C. Interior and the Prairies, it carries a bit more weight.
The "2" ratings: HSPF2 and SEER2
In 2023, the U.S. switched to updated test procedures that better reflect real installations, especially the extra fan power needed to push air through real ductwork. The results are called HSPF2 and SEER2. Many products sold in Canada now list both versions, and Canadian regulators have proposed aligning with the new metrics.
| Rating | What it measures | Rough relationship to older rating | Good value for Canada (approx.) |
|---|---|---|---|
| HSPF (Region IV) | Seasonal heating, moderate climate | — | 10+ |
| HSPF2 (Region IV) | Seasonal heating, updated test | Roughly 15% lower than HSPF | 8.5+ |
| SEER | Seasonal cooling | — | 16+ |
| SEER2 | Seasonal cooling, updated test | Roughly 4–5% lower than SEER | 15+ |
| COP at -15°C | Instant heating at cold temperature | Not seasonal | 1.75+ |
Conversions are approximate and vary by product type. Ducted and ductless units convert differently.
The key point: an HSPF2 of 8.5 is not worse than an HSPF of 10. They're on different scales. Compare HSPF2 to HSPF2.
What matters most for cold climates
Headline seasonal ratings don't tell you how a heat pump behaves at -25°C. For Canadian winters, look for:
- Capacity at low temperatures. How many BTUs per hour the unit still delivers at -15°C, -20°C or -25°C, compared with its rated capacity at 8°C. Cold-climate units often keep 70–100% of rated capacity at -15°C.
- COP at -15°C (5°F). ENERGY STAR's cold-climate designation requires a COP of at least 1.75 at that temperature.
- Minimum operating temperature. Many cold-climate models list -25°C to -30°C.
- Variable-speed (inverter) compressors. These adjust output smoothly and are standard on most cold-climate equipment.
Independent product lists from efficiency organizations publish this low-temperature data. Ask your installer to show you the figures for the exact indoor and outdoor model pairing they're quoting, because ratings apply to matched systems. Our glossary defines terms like balance point and design temperature if you want to go deeper.
Putting the numbers to work
When you compare quotes:
- Check that the ratings are for the matched pair of indoor and outdoor units.
- Prioritize HSPF/HSPF2 and low-temperature capacity over SEER.
- Look at sizing alongside efficiency. An efficient unit that's too small leans on backup heat. One that's too large short-cycles in mild weather.
- Remember the house matters. Air sealing and insulation reduce the load so a smaller, cheaper unit can do the job. Our whole-home upgrade sequence explains the order.
Rebate programs often set minimum efficiency or cold-climate requirements. Check current programs for your address with the rebate finder.
Frequently asked questions
What is a good HSPF for a heat pump in Canada?
As a rough guide, an HSPF (Region IV) of 10 or more, or an HSPF2 of about 8.5 or more, is a solid efficiency level. Pair it with confirmed capacity and a COP of at least 1.75 at -15°C for cold regions.
Why is my heat pump's COP lower on cold days?
The colder the outdoor air, the larger the temperature gap the heat pump has to bridge, so it needs more electricity per unit of heat. Even so, a cold-climate unit at -20°C usually beats electric resistance heat.
Is EER the same as SEER?
No. EER measures cooling efficiency at a single hot condition, while SEER averages across a cooling season. EER is mostly relevant in very hot climates.
The bottom line
COP tells you efficiency at a moment, HSPF tells you heating efficiency over a season, and SEER does the same for cooling. Watch for the "2" versions, which use a different scale. In Canada, give the most weight to heating ratings and cold-weather capacity, and make sure the numbers you compare are for the exact system you'll be installing.
Sundamentals is an independent, non-profit education platform. Program details and prices change often — check current programs for your address in our rebate finder.