Heat Pump Not Heating in Winter? 7 Causes and When to Call a Pro
If your heat pump isn’t heating in winter, the cause is often simple. A wrong setting, a dirty filter or snow on the outdoor unit can all leave your home cold. Other problems, like low refrigerant or a failed part, need a licensed technician. This guide covers the seven most common causes, what you can check yourself and when to call for heat pump repair in Halifax. Wet snow, freezing rain and salty ocean air make winter tough on heat pumps in Halifax. Clim A.G has been installing, repairing and servicing heat pumps across the city with over 13 years of experience.
7 Common Causes of a Heat Pump Not Heating
Here are the most common reasons a heat pump stops heating.
1. Wrong Thermostat or Remote Setting
Your system may be set to cool, dry or fan mode instead of heat. Switch it to heat, raise the temperature a few degrees and put new batteries in the remote. Also make sure a schedule or eco mode isn’t turning the temperature down. If everything looks right but the unit still won’t respond, the thermostat may need to be checked.
2. A Clogged Air Filter
A dirty filter blocks airflow, so less warm air reaches your rooms. It also makes the system work harder, which raises your power bill. Take the filter out, rinse or replace it, then let it dry before putting it back. Check it every month or two during the heating season. If airflow is still weak after cleaning, the indoor coil may need a professional cleaning.
3. Snow Around the Outdoor Unit
One heavy storm can bury an outdoor unit. Without airflow, it can’t pull heat from the outside air. Brush away loose snow gently, then keep the area around the unit clear. If the unit is covered in solid ice, don’t chip at it, since sharp tools can damage the coil. A raised stand helps keep the unit above drifting snow.
4. A Tripped Breaker
Your heat pump has its own breaker in the electrical panel, plus a shut-off switch near the outdoor unit. Reset the breaker once and check that the switch is on. If the breaker trips again, leave it off. Repeated trips usually mean an electrical problem, such as a loose wire or a worn breaker. These problems often show up in winter, when the system runs the most.
5. A Faulty Defrost System
In cold weather, your heat pump runs a defrost cycle to melt frost off the outdoor coil. This usually takes a few minutes, often with a puff of steam. A little frost is normal. Thick ice that never melts means the defrost system may have failed. First, make sure water from the roof or gutter isn’t dripping onto the unit. If ice keeps building up for more than a day, a sensor or control board is likely the cause.
6. Low Refrigerant
If refrigerant leaks out, your heat pump keeps running but only blows lukewarm air. Look for hissing sounds, oily spots on the lines or ice on the copper pipes. Only a licensed technician can find the leak and add refrigerant safely. A leak left too long puts extra strain on the compressor, which can turn a small fix into a costly repair.
7. A Worn-Out Part
Parts like the reversing valve, compressor or capacitor can wear out over time. Salt air near the coast can also speed up rust on outdoor parts. If the unit hums but won’t start or makes grinding noises, turn it off at the breaker. For an older system that keeps breaking down, ask your technician if a new heat pump installation would cost less in the long run.
When to Call a Pro
Call for heat pump repair if you notice:
- Cool air that won’t stop, even after checking the basics
- Ice that won’t melt or keeps coming back
- A breaker that trips more than once
- Hissing, grinding or a burning smell
Until help arrives, use backup heat like baseboards or a furnace. Don’t open the outdoor unit’s panels yourself. Never use fuel-burning heaters indoors.
Final Thoughts
Most of the time, a heat pump that isn’t heating has a simple cause, like a setting, a filter, snow or a breaker. If the heat doesn’t come back or you notice ice, odd noises or a breaker that keeps tripping, call a licensed technician. Booking heat pump maintenance each fall can also catch many of these problems before winter. Clim A.G with 13 years of experience provides heat pump repair, servicing and installation for homes across Halifax.