Air-conditioner with a dual-refrigerant circuit

摘要

An air-conditioner having a dual-refrigerant cycle includes a primary refrigerant circuit (10) heat-exchanged (16) with outdoor air; a secondary refrigerant circuit (12) heat-exchanged (40) with indoor air to perform either a cooling operation or a heating operation; and a heat exchange unit (14) disposed between the primary refrigerant circuit and the secondary refrigerant circuit to perform heat exchange therebetween, wherein the secondary refrigerant circuit (12) includes a compressor (42) for compressing a refrigerant circulating in the secondary refrigerant circuit. A condensing pressure of the primary refrigerant circuit is lowered during the heating operation and an evaporation pressure of the primary refrigerant circuit is increased to thereby enhance efficiency of the air-conditioner.