To stabilize a refrigerating cycle by preventing or reducing an overheat of an intermediate part of an indoor heat exchanger when cooled and to control to an optimum refrigerant flow rate under the stabilized control of a valve travel of an expansion valve.

A refrigerant flow rate controller 11 controls a valve lift of an electronic expansion valve 4 so that a superheat degree becomes a predetermined target value. In this case, the superheat degree is obtained by a difference between a lower temperature by comparing a temperature of an intermediate part of an evaporator detected by an evaporator intermediate part temperature sensor 10 at the time of cooling in the refrigerating cycle with an evaporator inlet temperature detected by an evaporator inlet temperature sensor 9 and a compressor suction temperature detected by a compressor suction temperature sensor 7.