Common Electrical Problems with Heat Pumps

Heat Pump Electrical Problems - Pacific Heating Cooling

heat pump is a great alternative to other HVAC systems such as gas furnaces and boilers, providing cooling in the summer and heating in the winter. They are basically air conditioners that can reverse themselves to provide heating as well.

While they are great alternatives to furnaces, boilers, and other heating systems, helping you save money and energy, they can also present some difficulties, such as electrical problems.




Sometimes your heat pump will malfunction or fail to turn on at all if there are issues with the wiring, loose terminals, or damaged circuit breakers/fuses.

If the connections in the heat pump itself or in the wiring that connects the heat pump to your breaker/fuse box are damaged, you will need a professional to diagnose and fix the situation.

Before you assume the worst, however, make sure you check all of the power switches to your equipment to ensure they are on. These switches include the thermostat, the breaker/fuse box, and the typical electrical power switch.

If your heat pump won’t turn on:


If your heat pump won’t turn on at all, one of the first things you should check is the breaker/fuse box.

For breaker boxes, look for the breaker that is in a different direction from the rest of the breakers. This is the tripped breaker. To restore power to the heat pump, flip the breaker to the full “off” position before flipping it to the full “on” position.

For fuse boxes, you want to look for the damaged fuse. This should be easy to spot. Simply look for the fuse that is discolored (usually a purplish, brownish color) or with a piece of melted metal inside. Once you identify the blown fuse, unscrew it and replace it with an exact replacement. If you need to purchase a replacement, take your fuse to a local home improvement store and find a perfect match (same type and amperage).

If after you restore power at the breaker/fuse box, the fuse blows or breaker trips again, don’t restore power until a professional HVAC technician has had a chance to diagnose and repair the problem. Frequently tripped breakers and blown fuses are signs of a more serious electrical problem.


After resetting power at the breaker/fuse box, make sure the power switch near your heat pump is flipped on. Sometimes, it will have been accidentally flipped off. The switch is normally located near the heating equipment itself. There may also be a second electrical switch outside of the home, near your outdoor heat pump unit. Make sure these heat pump switches are turned on.


If all of the switches are turned on and power is flowing through your electrical panel, the last electrical switch you want to check is the thermostat. Make sure the control is set to HEAT (for heating), COOL (for cooling), and the FAN to AUTO. If you want heat, set the temperature to a high setting (above the room temperature). If you want cooling, set the temperature lower than the room temperature.


The fan or blower motor inside your indoor air handling unit is responsible for blowing the conditioned area into your duct system and throughout your home. When you need heating or cooling, the fan is the main part that distributes the air, and it runs on electricity.

If the fan is not receiving electrical power, the fan won’t turn on at all and air won’t be able to move through your home. Contact a professional HVAC technician if your fan motor is making strange noises or not working at all.


Your air conditioner or heat pump compressor has an important job. It applies pressure to the refrigerant and then moves the refrigerant into compressor coils, where it is then transformed into a liquid state. If the compressor motor won’t run, which relies on electricity, then the compressor won’t work and the entire process will start malfunctioning.

You may notice your compressor acting up if the heat pump starts short-circuiting and not properly conditioning the indoor air. Compressor problems are not something you can fix on your own. If you notice a problem with your compressor motor, contact a professional HVAC technician right away.



  • Double-check that you have your thermostat set to “heat” or “cool” (depending on your needs) and the fan setting is set to “auto.”
  • Make sure all of the switches are turned on, including at the breaker/fuse box.
  • Check the air filter and replace it if necessary (write the date of replacement on the air filter and never wait more than 90 days to replace or clean the filter)
  • If you have an indoor fan motor belt, make sure it is not too loose.
  • Check for leaks around your indoor and outdoor units for any leaking refrigerant. You may need to repair the leak and recharge your refrigerant (call a professional)
  • Make sure you schedule routine heating and cooling maintenance every year (ideally, once in the fall for heating and once in the spring for cooling).

If you have checked all of the common electrical problems with heat pumps and your heat pump is still giving you problems, you may have an electrical problem with loose terminals and the wiring.

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