Describes the heating performance of a four-ton gas-engine-driven heat pump (GEHP) and includes a brief description of the engine used. Concentrates on the unique refrigerant heater used in the system, which maximises the heating performance of the GEHP, particularly at low ambient temperatures.

KEYWORDS: performance, gas engine heat pumps, heat pumps, refrigerants, R22, heaters, low temperature, ambient temperature, coefficient of performance, heating, cooling, electricity consumption, gas consumption, energy consumption, compressors, thermal capacity, Japan