How to Repair a Refrigerator Defrost Heater How to Repair a Refrigerator Defrost Heater

What You'll Need
Warm Towel
Replacement defrost heater

All refrigerators will contain a defrost heater. Sometimes the refrigerator cools too much or doesn’t cool at all. This can be caused by a broken defrost heater as this will regulate the temperature of the fridge to keep food cold. It is not necessary to get a new refrigerator but simply fix or replace the broken defrost heater.

Step 1 – Location

To replace the heater, unplug the fridge and find the defrost heater. Before accessing the heater, take out any food so there is plenty of room to work. The heater can be located in 1 of 2 places; underneath the freezer door floor, or behind the fridge's back panel.

Step 2 – The Timer

Sometimes it is only the timer that is broken. Look for the advance screw. Turn this clockwise to advance the timer. Wait about 30 minutes to see if a change has happened. If the timer has not advanced, then it should be replaced. If the replaced timer still does not cause the heater to work, then the heater is most likely broken and will need to be replaced.

Step 3 – Temperature Setting

Check that the temperature setting has not accidentally been changed. Depending on where the dial is, a jar or a container that has shifted may have changed the temperature to a higher temperature. Reset the temperature and listen for the defroster to start. If it does not immediately start, then there are additional problems.

Step 4 – Air Flow

Ensure that the air flow around the vents are not blocked. This can cause the system to malfunction and the interior will not reach the desired cool temperature. Always make sure the vents are not blocked and that air can easily circulate in the fridge and freezer.

Step 5 – Check the Condenser Coil

These coils should be cleaned at least once a year, as particles in the air can become deposited on the coils and cause operating problems when the buildup is great enough. This can easily be cleaned by vacuuming the coils and brushing away any dirt with a cloth or a brush. A narrow paint brush can get rid of dirt in hard to reach places.

Step 6 – Wire Connections

Make sure that the wires are not twisted or kinked. In order that the wires have a secure connection, use zip ties or the original connectors. Make sure that all the wires are properly covered, as the heat and condensation will cause issues with the electrical connections.

Step 7 – Thermostat

The defroster may not be working properly, because the thermostat in the refrigerator is probably faulty and not giving the heater the proper temperature. Pull out the thermostat where it is found, near the temperature switch and see if the heater works when the thermostat is out. Sometimes the thermostat can be completely broken or a short circuit may have occurred in the wiring.


If you are not comfortable doing an appliance repairs yourself, then talk to a professional. This is a quick repair and the repairman can have it fixed quickly and easily as long as the part is in stock. This is considered a minor repair and will cost about $200, depending on the refrigerator model. 

Got a New Project You're Proud of?

Post it on Your Projects!