The Whirlpool WP68233-3 Defrost Timer controls the refrigerator's automatic defrost cycle, preventing excessive frost buildup in the freezer. This 120V, 60Hz electrical component works like a timer, alternating between the cooling cycle and defrost heater at scheduled intervals. It activates the defrost heater for approximately 21 minutes after every 10 hours of compressor run time, a... https://www.partsmelange.ca/whirlpool-wp68233-3-defrost-timer-120v-60hz-for-refrigerator