Patent ID: 7503184

Claim:
A gas heat pump system having an engine compressor section, indoor section and outdoor section comprising: one or more refrigeration circuits comprising a refrigeration compressor and switching device, said switching device operable to direct refrigerant into the indoor section during a heating cycle and into the outdoor section during a cooling cycle; said engine compressor section comprising: an engine capable of running on a gaseous fuel; an engine cooling system; a fuel intake system; and an exhaust gas system; said indoor section comprising: an indoor heat exchanger; one or more fans operable to pass indoor air across the indoor heat exchanger; and one or more expansion valves corresponding to the indoor heat exchanger; said outdoor section comprising: a radiator; one or more outdoor heat exchangers; one or more fans operable to pass outdoor air across the radiator and the one or more outdoor heat exchangers; one or more expansion valves corresponding to each outdoor heat exchanger; and a control system operable to vary engine speed, number of refrigeration compressors running and blower speed in response to a thermostat setting.