US Patent 7392655 Vapor compression refrigerating device

In an automotive vehicle having a heater for a heating operation for a passenger room of the vehicle with use of waste heat of an engine, a vapor compression refrigerating device comprises a refrigerating cycle for a cooling operation for the passenger room. The vapor compression refrigerating device further comprises a heating cycle (a heat pump cycle, or a hot gas cycle) for performing a heating operation to engine cooling water by using the high temperature and high pressure refrigerant from a compressor device, wherein a control means activates the heating cycle at a predetermined time before starting an engine when an outside air temperature is lower than a predetermined value. Accordingly, the engine has been already warmed up before a driver gets into the vehicle.