Automatic freezer defrost systems are so common today that a buildup of frost in the freezer can be an unwelcome surprise. Wondering how you went from frost-free to a frozen mess? We’ll troubleshoot the most common reasons your freezer isn’t defrosting from incorrect temperatures to component failures.

Freezer Isn’t Defrosting? Here’s How to Troubleshoot the Problem

Though frost may seem like just a nuisance, it can affect the flavor of frozen foods and decrease your freezer’s efficiency. Here’s how to avoid these outcomes by troubleshooting the most likely reasons your freezer isn’t defrosting.

#1. Too Many or Not Enough Items

Having too much frozen food in a packed freezer can block airflow, allowing frost to form. Conversely, too few items can also result in frost buildup. A lack of frozen items makes it harder for the freezer to stay cold when the door is opened and warm air enters. The resulting mixture of warm and cold air can create frost.

These tips can help prevent a freezer icing up with too many or too few items:

  • Avoid overstocking the freezer to the point where airflow is limited or vents are blocked.
  • Make sure there are enough frozen items to help maintain a cold temperature.
  • Keep an inch of space between all frozen items and the freezer walls to allow for optimum airflow.

#2. Freezer Temperature Too Low

Does the ice buildup inside freezer look like fluffy snow? If this is the case, it’s likely due to a freezer temperature that’s too low. When its temperature is lower than it should be, there is less time for the freezer’s cooling cycle to remove any moisture in the air. As this moisture lingers it will take on a snowy appearance before the next cooling cycle begins.

Refrigerator maintenance tips include setting the freezer temperature no colder than 0°F. This can ensure optimal function and keep frost to a minimum.

freezer isn't defrosting

#3. Freezing Hot Foods

When it seems like your freezer isn’t defrosting properly, you may want to consider how you freeze food. Freezing hot food right away allows humidity to develop that will turn to frost on the freezer walls. When preparing to store food in the freezer, let it chill at room temperature until it’s no longer hot. Transfer the food to the refrigerator to finish cooling before placing it in the freezer.

#4. Freezer Door Left Open or Not Sealing

If the freezer door was left open too long, the mixture of warm and cold air can allow frost to develop. Always take care to close the door properly and avoid leaving it open for too long.

A faulty door seal can also be responsible for warm air entering and creating frost. If the seal becomes worn and brittle with time, the door won’t close properly and warm air will allow frost to form. Here’s how to assess the door seal when your refrigerator freezer will not defrost:

  • Check the seal for dirt and debris that could keep the door from closing properly. If the seal is very dirty, clean it with a paper towel and multipurpose cleanser and dry it thoroughly.
  • Test the seal by closing the door with a dollar bill halfway inside. If the bill can be pulled out with little resistance, the door seal is worn and requires replacement.

#5. Defrost System Failure

Is your freezer not defrosting even after these troubleshooting tips? If all else fails, it’s possible that one of the defrost system’s components has malfunctioned. The following part failures can cause defrosting issues:

  • Defrost Control Board: This component signals the freezer defrost cycle to start as needed. If it malfunctions, the cycle won’t turn on and frost will accumulate. If both the defrost heater and thermostat are working properly, the control board likely requires replacement.
  • Defrost Timer: The defrost timer turns on the heater when there is too much frost on the evaporator coils. To test the timer, advance the defrost dial to begin a cycle. If the defrost cycle takes more than 30 minutes, the timer is defective and must be replaced.
  • Defrost Heater: This mechanism provides the heat that defrosts the evaporator coils. If it’s malfunctioning, frost will continue to accumulate on the coils and in the freezer. If the heater shows a lack of continuity with multimeter testing, it needs to be replaced.

Cody’s Appliance Repair can help when your freezer isn’t defrosting properly. Call us for any refrigerator freezer repair.