ActronAir Crankcase Heater 75W (Metal) maintains compressor oil temperature during off-cycle periods on Hercules commercial systems, preventing refrigerant from migrating into the compressor sump and diluting the oil -- which causes bearing damage and premature compressor failure on the first start after a cold soak. The 75W Hercules crankcase heater provides higher heat output for the larger compressor sump volume in PKV1400T and PKV2000T Hercules commercial systems. Isolate power at mains before replacing any crankcase heater components.