Quick answer
Repair a heat pump that is under 10 years old with a small fault such as a capacitor, contactor, sensor, fan motor or defrost board. Replace it when it is 12 to 15 years old and the failed part is the compressor, the inverter board or a leaking coil that is out of warranty, or when the repair quote passes half the cost of a new system.
Whether you should repair or replace your heat pump comes down to three facts a technician can establish in one visit: how old the unit is, which part has failed, and whether that part is still under warranty. A heat pump works year-round, heating and cooling, so its typical life in Ontario is 12 to 15 years, shorter than a furnace. The closer you are to that range, the less a large repair makes sense.
The age-and-part rule for heat pump repairs
- Under 10 years, small electrical part: repair. A capacitor or contactor runs $150–$350, and most repairs on the outdoor unit land between $150 and $800, the same range as a central air conditioner because the parts are the same.
- Under 10 years, major part: check the warranty first. Registered equipment often carries long parts coverage on the compressor, which leaves you paying labour and refrigerant only. Your registration card or the serial number settles it.
- 10 to 12 years: repair anything minor, and get a replacement quote alongside any repair that needs the refrigerant circuit opened.
- 12 to 15 years or older with a failed compressor, inverter board or leaking coil: replace. These are the three most expensive parts in the machine, and the rest of the unit is the same age.
- Any age: replace when the repair quote is more than half the cost of a new system.
Why a refrigerant leak on an R-410A heat pump tips toward replacement
A leak repair costs more every year on an R-410A system, because that refrigerant is being phased down. New heat pumps have moved to R-32 and R-454B, and the two generations cannot be mixed: an R-410A unit can only be topped up with R-410A. Supply is shrinking while older units still need it, so the refrigerant is now a real part of the bill. Our guide to the R-32 and R-454B transition covers the change.
A proper leak job is more than a top-up. The technician, who must hold an ODP card to handle refrigerant, finds the leak, repairs or replaces the leaking component, pulls a vacuum and weighs in a full charge. A leak repair and recharge runs $300–$800 or more, and the total climbs when the leak is in a coil. On a 13-year-old unit, a new coil plus a full charge of a refrigerant on its way out is money spent on the wrong machine.
What replacement gets you that a repair cannot
A new cold-climate heat pump keeps producing useful heat at -25 °C, where an older single-stage unit hands the house over to backup heat well before that. The difference is the inverter compressor, which speeds up as the temperature falls. If your current unit leans on electric strips or the furnace through most of January, that is the gain you would feel.
- 3-ton cold-climate heat pump, installed: $9,500–$15,000.
- Across ducted and ductless systems of all sizes: $6,000–$16,000 installed before rebates.
- Rebates: the Home Renovation Savings Program from Enbridge Gas and Save on Energy pays on qualifying heat pump installations, never on repairs. Approval has to come before the install, and the installer must be on the program's participating-contractor list.
Is it safe to keep running a failing heat pump?
Usually yes for comfort problems, no for electrical ones. Shut the system off at the thermostat and the outdoor disconnect, and switch to your backup heat, if you see any of these:
- The breaker trips again after one reset.
- A burning smell at the outdoor unit or the air handler.
- Grinding or a hard metallic knock from the compressor.
- The outdoor coil is encased in ice that a defrost cycle does not clear.
A unit that still heats but runs longer, or one that steams for a few minutes during defrost, can wait for a booked appointment. Running a system that is low on refrigerant for weeks is the exception: it overheats the compressor and turns a leak repair into a compressor failure.
What happens on a heat pump repair-or-replace visit
The diagnostic visit is $90–$150 and is credited toward the repair if you go ahead. The technician tests the capacitor and contactor, the defrost sensors and board, the reversing valve, the refrigerant pressures and the compressor windings, then reads the serial number to date the unit and check its warranty status. You get the repair price in writing, and if the unit is past 10 years, a replacement price beside it.
How long a unit should last, and what shortens it, is covered in how long a heat pump lasts, and general figures are on the pricing page. ZK Mechanical services Mitsubishi, Fujitsu, Daikin and the major ducted brands from our Burlington shop. For heat pump repair in Burlington, Oakville, Milton, Hamilton or Mississauga, call (647) 801-1252 or book a diagnostic visit.