Fridge's Freezer Have Frost Buildup? All the Easy Fixes You Need to Know
Frost building up within the freezer can reduce the efficiency of your appliance and leave food too warm. The culprit may be a misaligned door, faulty defrost timer or a number of other problems. Our friends at Sears PartsDirect have some of the common fixes to get your fridge running at full speed.
Replace the Defrost Sensor
A defrost sensor, or defrost bi-metal termination thermostat, will trip when it detects that the temperature of the evaporator is reaching a level that may cause it to overheat. Once it trips, the power to the defrost heater shuts down. Frost can collect on the evaporator fins if the defrost sensor isn't working correctly, causing the freezer to lose cooling power. Get a volt/ohm meter to check for sensor continuity, and replace theis part if no continuity is shown around 0 degrees Fahrenheit.
Repair the Defrost System
Your fridge's defrost system improves heat exchange by occasionally melting frost from the evaporator. This prevents ice from building up and blocking airflow in the appliance. When there is an issue, the ice will not melt, harming both the fresh food and freezer sections of your refrigerator. If the defrost system is broken, diagnose the root cause first before repairing.
Replace the Electronic Control Board
The electronic control board is an essential piece to any fridge. Also commonly known as the main control board or the power control board (PCB), this part controls the compressor and defrost cycle. It senses when the refrigerator needs to be cooled, sending power to the compressor and fans. The control board also works with the sensor to maintain temperature in the both the fridge and freezer, helping control a proper defrost cycle. Run a diagnostic test to check if the electronic control board is malfunctioning. Tests can vary by make or model, so check your owner's manual or tech sheet for more information.
Adjust the Refrigerator or Freezer Door
If the freezer door hinge has been bent or dented, it may cause the door to sag. This compromises the seal, allowing warm air into the freezer. This moist air may cause excessive frost to form on the drain tube causing it to freeze. Adjust or replace the hinges so the door shuts and seals properly.
Replace the Defrost Timer
Your fridge's defrost timer controls the intervals between automatic defrost cycles. It makes sure the compressor is off before turning on the defrost heater temporarily to melt frost off the evaporator fins, allowing an efficient exchange of heat. Once the defrost cycle ends, the timer turns off the defrost heater to continue regular cooling. When this part isn't working properly, the defrost heater will run constantly or not run at all.