A computing device calculates a quality of a refrigerant flowing out of a second expansion device on the basis of an inlet liquid enthalpy calculated on the basis of a temperature of the refrigerant flowing into the second expansion device and a saturated gas enthalpy and a saturated liquid enthalpy calculated on the basis of a temperature of the refrigerant flowing out of the second expansion device or a pressure of the refrigerant sucked into a compressor; calculates a liquid-phase concentration and a gas-phase concentration of the refrigerant flowing out of the second expansion device on the basis of the temperature of the refrigerant flowing out of the second expansion device and the pressure of the refrigerant sucked into the compressor; and calculates a composition of the refrigerant circulating in a refrigeration cycle on the basis of the calculated quality, liquid-phase concentration, and gas-phase concentration.