The Refrigerator Defrost Heater Assembly keeps the cooling coils from freezing and ensures the heat next to the cooling coils has reached the desired temperature. If your appliance isn't cooling properly, replacing this part may alleviate the issue. Note that you should check continuity with a multi-meter before installing the new part. Replacing this part will require basic hand tools, some disassembly of the appliance and novice repair experience. You must unplug the appliance or shut off the house circuit breaker before installing this part.