Heat Pump Repair
Heat pumps are different beasts than furnaces and standard ACs. They run year-round (heating in winter, cooling in summer), they have more sophisticated controls, and they're working hardest during the most demanding weather. When something goes wrong on a cold-climate heat pump, it requires technicians who actually understand the system — not just generalists who learned heat pumps as an afterthought.
Our technicians are trained on the cold-climate inverter systems that work in Ontario: Mitsubishi Hyper-Heat, Daikin Aurora, Carrier Infinity, Lennox Signature, Trane XV20i, and the major ductless brands. We diagnose properly, repair in a single visit when possible, and don't push replacement when a $400 component fix solves the problem.
When you need heat pump repair
Common heat pump issues we diagnose across Halton Hills:
- Heat pump not heating in cold weather — could be a frozen outdoor coil that's not defrosting properly, a refrigerant issue, a reversing valve fault, or a controls problem.
- Heat pump not cooling in summer — same diagnostic approach as a standard AC: refrigerant levels, capacitor health, contactor, condenser cleanliness.
- Outdoor unit caked in ice — not just frost. A working heat pump runs defrost cycles every 30–90 minutes in cold weather. Ice buildup that doesn't clear means defrost isn't working.
- Error codes on the indoor air handler or thermostat — modern heat pumps self-diagnose. Most error codes have specific meanings that point straight at the failing component.
- Outdoor unit running constantly without producing heat — the system is in an emergency-heat or auxiliary-heat mode, often because the outdoor unit isn't able to extract heat.
- Refrigerant noises or low refrigerant — heat pumps use the same refrigerants as AC systems. Refrigerant doesn't 'get used up' — if you're low, there's a leak that needs proper repair.
- Performance degradation over time — heat pump 5+ years old that doesn't seem to heat as well as it used to. Often a refrigerant slow-leak issue, fouled outdoor coil, or capacitor wear.
How a heat pump repair call goes
- 01
Pre-arrival triage
When you call, we ask about symptoms, error codes, what the system was doing before failure, and any recent weather conditions. This often points us toward the likely cause before we arrive — and helps us prioritize the visit (no-heat calls jump ahead of cooling-not-cool-enough calls).
- 02
Systematic diagnosis
We don't jump to part replacement. The diagnosis runs through the controls (thermostat, control board), refrigerant pressures, electrical components (capacitors, contactors, fan motor), defrost cycle operation, and reversing valve function. Most heat pump issues are diagnosable in 30–60 minutes.
- 03
Repair with right parts
We carry common heat pump repair parts on the truck — capacitors, contactors, defrost sensors, and the more frequently-failing components. For specialized parts, we order and return — usually within 2–4 business days. We don't keep the system out of service longer than necessary.
- 04
Verification and education
After the repair, we run the system through full heating and cooling cycles, verify performance against design specs, and walk you through what was wrong and what you can watch for. Heat pumps are unfamiliar enough to most homeowners that 5 minutes of explanation goes a long way.
Heat pumps we service
We work on every major cold-climate heat pump brand sold in Ontario, including the older variable-capacity systems still in service:
What heat pump repair costs in Halton Hills
Diagnostic visit: $140–$190, waived if you proceed with the recommended repair. Common heat pump repairs:
- Capacitor replacement: $280–$450
- Contactor replacement: $320–$480
- Defrost sensor replacement: $300–$450
- Refrigerant top-up + leak diagnosis: $400–$700
- Reversing valve replacement: $900–$1,800 (heat-pump-specific component)
- Control board replacement: $500–$1,400 depending on system
- Compressor replacement: $2,200–$4,500 — at this point on a unit older than 8–10 years, replacement of the entire system is usually the better call
Heat pump compressor replacement specifically is rarely the right move on an older system — refrigerant migration during the swap can damage other components, and the new compressor's warranty doesn't extend to the rest of the aging unit. We'll be honest with you about the math when this comes up.
Heat Pump Repair questions
Why is my heat pump iced up?
Some frost on the outdoor coil in winter is normal — heat pumps run periodic defrost cycles to clear it. Heavy ice buildup that doesn't clear, on the other hand, indicates a defrost cycle problem: a failed defrost sensor, a stuck reversing valve, low refrigerant, or a control board fault. Ice should never accumulate to the point of blocking the fan or covering the entire coil — that's a service call.
My heat pump is making strange noises in winter. Is something wrong?
Heat pumps make different sounds than furnaces and ACs, and homeowners new to heat pumps often misinterpret normal operation as failure. Defrost cycles include a momentary 'whoosh' as the reversing valve switches, which is normal. Concerning sounds: continuous grinding (motor bearings), banging on startup (loose components), squealing (blower bearing), or a high-pitched whine that wasn't there before (refrigerant or compressor issue).
Why does my heat pump struggle below -15°C?
Modern cold-climate heat pumps are rated to deliver full capacity at -15°C and operate to -25°C and below. If yours is struggling above -15°C, the most likely causes are: (1) low refrigerant from a slow leak, (2) outdoor coil fouled with debris or ice, (3) wrong sizing for the home (oversized or undersized), or (4) older non-cold-climate equipment that wasn't designed for our climate.
My utility bill is higher this winter than last winter. Could the heat pump be the problem?
Possibly. A heat pump losing efficiency over time — typically from refrigerant slow-leaks, fouled coils, or component drift — uses more electricity to deliver the same heat. A 15–25% performance drop is invisible on the thermostat but very visible on the electric bill. A diagnostic visit can confirm whether the heat pump is the cause.
Do you handle ductless mini-split repair too?
Yes — ductless mini-splits are heat pumps, just configured differently from ducted systems. The diagnostic approach and most repair techniques are the same. We carry parts for the major ductless brands (Mitsubishi, Daikin, LG, Fujitsu, Gree, Senville).
Should I repair my old heat pump or replace it?
Heat pump compressor replacement is usually a poor decision on systems over 8 years old. The compressor is the most expensive single component, and replacing it on an aging system rarely returns the equipment to like-new performance for long. For heat pumps over 10 years old with major component failure, replacement is almost always the smarter call — current cold-climate models are more efficient than what they're replacing, and you reset rebate eligibility.
Ready to book heat pump repair?
Call us or submit a quick request. We'll get back to you within an hour during working hours.
Mon–Fri 7:00 AM – 7:00 PM · Saturday 8:00 AM – 5:00 PM · 24/7 emergency service available