Abstract: An air conditioning device has a heat source unit and a utilization unit connected via a refrigerant connection pipe to form a refrigerant circuit, and has a cooler, a secondary receiver, and a separation membrane device. The cooler cools at least a portion of the refrigerant that flows through the liquid-side refrigerant circuit as the compressor is operated and the refrigerant in the refrigerant circuit is recirculated. The secondary receiver separates the refrigerant cooled by the cooler into a liquid refrigerant and a gas refrigerant that includes non-condensable gas. The separation membrane device has a separation membrane for separating the non-condensable gas from the gas refrigerant obtained by gas-liquid separation, and discharges the non-condensable gas thus separated to the outside of the refrigerant circuit.