Short answer: a heat pump that is locked in solid ice, blowing cool air for more than a few minutes, tripping its breaker or not running at all needs a technician. Call Aire One Peel at 905-564-8545. We diagnose the fault, give you a written quote before any repair starts and, when the part is on the truck, finish the repair in the same visit.
Aire One Peel Heating & Cooling is a Carrier Factory Authorized Dealer with its head office at 1625 Courtneypark Dr E in Mississauga. Our factory-trained technicians repair and maintain ducted and ductless heat pumps of all major makes and models, including cold-climate systems, for homes and businesses across Mississauga and Peel Region. Our phone line is answered 24 hours a day, 365 days a year for emergency repairs.
Last reviewed: September 18, 2026 · Carrier Factory Authorized Dealer · 4.9-star Google rating · Refrigerant work only by certified refrigeration mechanics (313A or 313D), as Ontario requires
Heat Pump Repair Services in Mississauga
Every repair visit starts with a full diagnostic rather than a guess. The technician checks the thermostat and controls, the filter and airflow, the outdoor unit (fan, coil and defrost operation), electrical parts such as capacitors and contactors, and the refrigerant pressures. You then get a written quote, and you decide what goes ahead. If a major repair or a replacement turns out to be the better choice, financing is available.
What we repair
- Defrost faults: an outdoor unit locked in ice, failed defrost sensors or control boards.
- No heat, or cool air in heating mode: a stuck reversing valve, a low refrigerant charge or auxiliary heat that does not engage.
- Refrigerant leaks: leak search, repair and recharge, done only by certified refrigeration mechanics.
- Electrical and control faults: capacitors, contactors, control boards, thermostats and breakers that trip.
- Fan and compressor problems: outdoor fan motors, indoor blowers and compressors that struggle to start.
- Ductless (mini-split) faults: error codes, and indoor units that leak water or stop responding.
Common Heat Pump Problems in Mississauga Homes
Two things that look like breakdowns are normal. In cold, damp weather the outdoor unit defrosts itself several times a day: the fan stops, steam rises and the indoor air runs cooler for a few minutes. And the air from a heat pump always feels milder than the blast from a gas furnace. If the house holds its set temperature, the system is working. The problems below are the ones worth a call.
| Symptom | Likely cause | What to do |
|---|---|---|
| Outdoor unit locked in solid ice | Defrost failure, or water draining onto the unit | Switch the system off and let it thaw. Never chip ice off the coil. Book a repair. |
| House losing temperature in a cold snap | Auxiliary heat not engaging, or a failed component | Call the same day. |
| Cooling in heat mode, or heating in cool mode | Stuck reversing valve | Book a technician. |
| No heating or cooling at all | Thermostat mode, a tripped breaker or a failed part | Check the thermostat and reset each breaker once. If a breaker trips again, leave it off and call. |
| Turns on and off every few minutes | Clogged filter, thermostat fault or a refrigerant problem | Replace the filter. If the short cycling continues, book a repair. |
| Grinding, buzzing or rattling | Worn fan motor, loose panel, debris or a failing electrical part | Switch the system off and call. Running it can turn a small repair into a large one. |
For the five free checks to try before you call, see why your heat pump is not working.
Call right away if you notice any of these:
- A burning smell, or a breaker that trips a second time: switch the system off at the breaker and call. Do not reset it again.
- Solid ice that comes back: the outdoor unit ices over again after you have let it thaw.
- The house cannot hold its set temperature in cold weather, or the auxiliary heat runs constantly in mild weather.
- Water leaking from the indoor unit or the air handler.
Emergency Heat Pump Repair in Mississauga
A heat pump that fails in a cold snap is an emergency, and our line is answered 24 hours a day. When you call 905-564-8545 we ask what the system is doing, tell you what to switch off and book the earliest available visit. If the house is losing heat and your thermostat has an emergency or auxiliary heat setting, use it until the technician arrives. It costs more to run, so switch back to normal heating once the repair is done.
Heat Pump Maintenance and Tune-Ups
Most winter breakdowns start as small problems in the fall: a weak capacitor, a dirty coil or a defrost sensor drifting out of range. A heat pump heats in winter and cools in summer, so it runs roughly twice the hours of an air conditioner, and a yearly tune-up matters more, not less. The visit covers cleaning the coils, checking refrigerant pressures and defrost operation, testing electrical parts and confirming airflow. Our protection plans include an annual preventative maintenance and tune-up, and documented maintenance also protects your warranty; see our guide to heat pump warranties in Ontario.
Repair or Replace Your Heat Pump?
Repair usually makes sense when the unit is less than about 10 years old, the fault is a single part and the system kept the house comfortable before it failed. Replacement is worth pricing when the unit is 12 to 15 years old or more, needs a compressor or a major refrigerant repair, or runs on R-22 refrigerant, which is no longer produced or imported in Canada. Replacement estimates are free, so you can compare both options before you decide. If you do replace, see heat pump installation in Mississauga, the cost to install a heat pump in Ontario and the current HVAC rebates in Ontario.
Heat Pump Repair Across Peel Region
From our Mississauga head office we repair heat pumps in Brampton, Caledon, Milton, Etobicoke, Georgetown and Bolton. New to heat pumps? Start with our heat pumps in Mississauga overview, or read how they perform in cold Ontario weather.
Heat pump not keeping up? Call 905-564-8545, or book a repair visit online.
Heat Pump Repair FAQ
Call for a repair if the house cannot hold its set temperature, the outdoor unit is locked in solid ice, the system trips its breaker, turns on and off every few minutes, makes grinding or buzzing noises, or your electricity bill jumps without a change in the weather. Steam during a defrost cycle and mild supply air are normal.
During a defrost cycle the system briefly runs in reverse, so the indoor air feels cool for a few minutes. That is normal. If the cool air continues, or the house is losing temperature, the likely causes are a stuck reversing valve, a low refrigerant charge or auxiliary heat that is not engaging, and the system needs a technician.
Light frost that comes and goes is normal, because the defrost cycle clears it. A solid block of ice that stays is a defrost failure or a drainage problem. Switch the system off, let it thaw, never chip the ice off the coil, and book a repair.
Common repairs such as capacitors, contactors, sensors and fan motors are usually finished in a single visit when the part is on the truck. Compressor, reversing valve and refrigerant leak repairs take longer and can need a second visit for parts.
You can safely check the thermostat, reset each breaker once, replace the filter and clear snow and leaves from around the outdoor unit. Anything involving refrigerant, the reversing valve, defrost controls or wiring is not a do-it-yourself job. In Ontario, refrigerant work is restricted to certified refrigeration mechanics under O. Reg. 463/10.
Repair usually makes sense when the unit is less than about 10 years old and the fault is a single part. Replacement is worth pricing when the unit is 12 to 15 years old or more, needs a compressor or a major refrigerant repair, or runs on R-22 refrigerant. Replacement estimates are free, so you can compare both options.
Yes. Our line is answered 24 hours a day at 905-564-8545, and we book the earliest available visit. If the house is losing heat, use the emergency or auxiliary heat setting on your thermostat until the technician arrives.
We repair all major heat pump brands, ducted and ductless, and we are a Carrier Factory Authorized Dealer. From our Mississauga head office we cover Mississauga, Brampton, Caledon, Milton, Etobicoke, Georgetown and Bolton.