An air conditioner (10) includes a refrigerant circuit (13) and refrigerant. The refrigerant circuit (13) has a compressor (1), a condenser (2), a pressure-regulating valve (3), and an evaporator (4). The refrigerant is R32. The pressure-regulating valve (3) includes a flow path (33) causing the refrigerant flowing from the condenser (2) to flow to the evaporator (4), a pressure reference chamber (S2) partitioned from the flow path (33) and filled with inert gas, and a valve portion (34) disposed in the flow path (33). The pressure-regulating valve (3) is configured to adjust a degree of opening of the valve portion (34) to adjust a flow rate of the refrigerant flowing through the flow path (33). The valve portion (34) is configured to increase the degree of opening when a pressure in the flow path (33) is higher than a pressure in the pressure reference chamber (S2), and reduce the degree of opening when the pressure in the flow path (33) is lower than the pressure in the pressure reference chamber (S2).