A crankcase heater is an electric heating element wrapped around the compressor to keep the oil warm and prevent refrigerant from mixing with it during the off-cycle. This ensures a "warm start" in the winter, which reduces friction and extends the compressor's life. This is a vital feature for heat pump systems operating in cold climates. Our Cooper&Hunter Hyper-Heat units use these to ensure reliable startup even at -22°F. Without a crankcase heater, the oil can become too thick to lubricate the moving parts properly. You can find these integrated into our multi-zone outdoor units designed for northern regions.