The Whirlpool WP61002992 Refrigerator Defrost Thermostat controls the defrost heater to prevent excessive frost buildup on the evaporator coils. It monitors the evaporator temperature and regulates electrical flow to the heater, allowing it to operate during the defrost cycle and stopping it when the required temperature is reached. This temperature control prevents overheating and su... https://www.partsmelange.ca/whirlpool-wp61002992-defrost-thermostat-for-refrigerator