The Aaon P83900 Crankcase Heater is a high-quality compressor protection component designed for HVAC and refrigeration systems. Rated at 480V and 90 watts with an 8-inch diameter, it works by maintaining warm oil temperature within the compressor crankcase to prevent refrigerant migration during off cycles. This heater is commonly used in rooftop units, packaged systems, and commercia... https://www.partshnc.com/p83900-aaon-480v-90w-8-dia-crankcase-heatr