A refrigeration apparatus comprising: a heat source unit including a compression unit and a gas-liquid separator; and a utilization unit (50, 60) as a utilization side apparatus, wherein the refrigeration apparatus performs a refrigeration cycle in which a high pressure is equal to or higher than a critical pressure of a refrigerant, the heat source unit constituting a refrigerant circuit connected to the utilization side apparatus, the heat source unit comprising: a plurality of heat exchangers (13, 17, 54, 64) including a radiator and an evaporator that constitute the refrigeration cycle of the refrigerant circuit, and a gas passage configured to communicate with a gas outlet of the gas-liquid separator and at least one of the plurality of heat exchangers (13, 17, 54, 64) provided in the refrigerant circuit; an opening and closing device configured to open and close the gas passage; and a controller, characterized in that: the controller is configured to close the opening and closing device when a pressure in the gas-liquid separator is equal to or less than a predetermined value in a state where the compression unit is stopped, and open the opening and closing device when the pressure in the gas-liquid separator is higher than the predetermined value, and the gas passage includes a second gas passage configured to communicate with the heat exchanger having functioned as the evaporator before the compression unit is stopped when the pressure in the gas-liquid separator is higher than the predetermined value. a heat source unit including a compression unit and a gas-liquid separator; and a utilization unit (50, 60) as a utilization side apparatus, wherein the refrigeration apparatus performs a refrigeration cycle in which a high pressure is equal to or higher than a critical pressure of a refrigerant, the heat source unit constituting a refrigerant circuit connected to the utilization side apparatus, the heat source unit comprising: a plurality of heat exchangers (13, 17, 54, 64) including a radiator and an evaporator that constitute the refrigeration cycle of the refrigerant circuit, and a gas passage configured to communicate with a gas outlet of the gas-liquid separator and at least one of the plurality of heat exchangers (13, 17, 54, 64) provided in the refrigerant circuit; an opening and closing device configured to open and close the gas passage; and a controller, characterized in that: the controller is configured to close the opening and closing device when a pressure in the gas-liquid separator is equal to or less than a predetermined value in a state where the compression unit is stopped, and open the opening and closing device when the pressure in the gas-liquid separator is higher than the predetermined value, and the gas passage includes a second gas passage configured to communicate with the heat exchanger having functioned as the evaporator before the compression unit is stopped when the pressure in the gas-liquid separator is higher than the predetermined value. a plurality of heat exchangers (13, 17, 54, 64) including a radiator and an evaporator that constitute the refrigeration cycle of the refrigerant circuit, and a gas passage configured to communicate with a gas outlet of the gas-liquid separator and at least one of the plurality of heat exchangers (13, 17, 54, 64) provided in the refrigerant circuit; an opening and closing device configured to open and close the gas passage; and a controller, a gas passage configured to communicate with a gas outlet of the gas-liquid separator and at least one of the plurality of heat exchangers (13, 17, 54, 64) provided in the refrigerant circuit; an opening and closing device configured to open and close the gas passage; and a controller, characterized in that: the controller is configured to close the opening and closing device when a pressure in the gas-liquid separator is equal to or less than a predetermined value in a state where the compression unit is stopped, and open the opening and closing device when the pressure in the gas-liquid separator is higher than the predetermined value, and the gas passage includes a second gas passage configured to communicate with the heat exchanger having functioned as the evaporator before the compression unit is stopped when the pressure in the gas-liquid separator is higher than the predetermined value. the controller is configured to close the opening and closing device when a pressure in the gas-liquid separator is equal to or less than a predetermined value in a state where the compression unit is stopped, and open the opening and closing device when the pressure in the gas-liquid separator is higher than the predetermined value, and the gas passage includes a second gas passage configured to communicate with the heat exchanger having functioned as the evaporator before the compression unit is stopped when the pressure in the gas-liquid separator is higher than the predetermined value.