Description: 4387503 Bimetal Defrost Thermostat stops the fridge from overheating during the defrost cycle by protecting the evaporator. This clip-on thermostat will sense the temperature increase in the evaporator during the defrost process, and will cycle the defrost heater off after the ice or frost is melted. The most common reasons for needing to replace this part are if your unit is leaking, has inconsistent temperatures (too hot or too cold), you are seeing buildup of ice, or your appliance is running too long. .
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