Incidence du choix du frigorigène sur les performances des pompes à chaleur aérothermiques.

Air is the cheapest and most readily available source of heat for heat pumps. This paper shows that air is often neglected as a heat source because of perceptions that air-source heat pumps are less efficient than other types of heat pumps. Calculations are presented to show that in an appropriate location with an appropriate refrigerant, the air-source heat pump can produce SEERs in excess of three. Refrigerants considered include ammonia (R717), Isobutane (R600a), R134a and R410A. It is shown that the most appropriate locations for air-source heat pumps are temperate places at high latitudes where the heating season is long and air temperatures rarely fall below 0°C. The United Kingdom is such a location. A design of air source heat pump capable of operating at very low temperature differences in the evaporator is described.