In short
HSPF2 is the seasonal heating efficiency rating on a heat pump: heat delivered over a test heating season divided by the electricity used. Higher is better. Divide it by 3.412 to get an average COP, so HSPF2 8.5 means about 2.5 units of heat per unit of electricity. In Ontario, compare the Region V figure, not the milder Region IV one.
HSPF2 is the heating number on a heat pump's rating sheet, the winter counterpart to the SEER2 cooling number printed beside it. When two heat pump quotes are on the table, it is the quickest way to compare how much electricity each will use over a winter. More rating terms are explained in the HVAC glossary.
What HSPF2 measures and how to turn it into a COP
HSPF2 is total seasonal heat output in BTU divided by total electricity in watt-hours. The '2' marks the M1 test procedure adopted in 2023, which assumes more realistic duct resistance than the old test. For the same equipment the HSPF2 figure is lower than the old HSPF: an HSPF2 of 8.5 is roughly the old HSPF 10.
Dividing HSPF2 by 3.412 converts it to a seasonal average COP, which is easier to picture.
- HSPF2 7.5 is a seasonal COP of about 2.2
- HSPF2 8.5 is a seasonal COP of about 2.5
- HSPF2 9.5 is a seasonal COP of about 2.8
- HSPF2 10 is a seasonal COP of about 2.9
Region IV vs Region V: why Canadian HSPF2 numbers look lower
The same heat pump has two HSPF2 values because the seasonal calculation depends on the climate it assumes. American brochures quote Region IV, a milder climate. Canadian ratings use Region V, which has more hours at low temperatures, so the identical unit scores lower. Before comparing two quotes, check that both figures are for the same region, or the one quoted honestly for Canada will look like the worse machine.
Rebate eligibility lists are built on these ratings. Ontario's Home Renovation Savings Program requires a cold-climate air-source heat pump to appear on Natural Resources Canada's qualified products list, so the model numbers on your quote need to match a listed combination exactly.
What HSPF2 does not tell you
HSPF2 is a seasonal average, so it says nothing about how much heat the unit makes on the coldest night. Two models with the same HSPF2 can differ widely in output at -15°C. For that, read the capacity and efficiency figures on the NEEP cold-climate listing. On a quote for an Ontario house, ask for all of these together:
- HSPF2 for Region V, the heating season rating
- SEER2, the cooling season rating on the same label
- Maximum heating capacity at -15°C, in BTU per hour
- COP at -15°C
- What provides backup heat and at what outdoor temperature it takes over
SEER2 is a different rating with its own rules, covered in what SEER2 is and what rating you need in Ontario. The rated HSPF2 also assumes a correct installation. Wrong refrigerant charge, restrictive ducts or a thermostat that brings on electric backup too early will all pull the real-world figure down.
What a high-HSPF2 heat pump costs to install
A cold-climate heat pump in Ontario typically costs $6,000–$16,000 installed before rebates, depending on capacity, ducted or ductless layout and electrical work. A 3-ton cold-climate system commonly lands at $9,500–$15,000. Models with the highest HSPF2 use variable-speed compressors and sit toward the top of those bands.
A decision rule that holds up: once a model meets the cold-climate specification, choose on capacity at -15°C and on the installer's heat-loss numbers before paying extra for another few tenths of HSPF2. ZK Mechanical lists both ratings and the model combination on every heat pump installation quote. To compare two quotes you already have, send them over.
Questions people ask about HSPF2
What is a good HSPF2 rating in Ontario?
The NEEP cold-climate specification sets its floor at HSPF2 7.7 for ducted heat pumps and 8.5 for ductless, measured on the Region IV scale. A unit at or above those figures is a sound starting point. Past that, how much heat the unit still produces at -15°C matters more to an Ontario winter than a slightly higher seasonal number.
Is HSPF2 the same as HSPF?
No. Both describe seasonal heating efficiency, but HSPF2 comes from a tougher test and produces lower numbers for the same equipment. An older heat pump rated HSPF 10 would score around 8.5 on the newer scale. Do not compare the HSPF on a ten-year-old unit's label directly with the HSPF2 on a new quote.
Does a gas furnace have an HSPF2 rating?
No. HSPF2 applies only to heat pumps. A gas furnace is rated by AFUE, the percentage of the fuel's energy that becomes heat for the house. In a hybrid system each half has its own rating: HSPF2 for the heat pump and AFUE for the furnace. The control setting that decides which one runs is the changeover temperature.