Refrigeration apparatus

A refrigeration apparatus that uses a refrigerant that operates in a supercritical range, the refrigeration apparatus comprising:

• a compression mechanism having a plurality of compression elements arranged and configured so that refrigerant discharged from a first-stage compression element of the plurality of compression elements is sequentially compressed by a second-stage compression element;
• a heat source-side heat exchanger using air as a heat source and being arranged and configured to operate as a radiator or evaporator of refrigerant;
• a usage-side heat exchanger arranged and configured to operate an evaporator or radiator of refrigerant;
• a switching mechanism arranged and configured to switch between a cooling operation state in which the refrigerant is circulated through the compression mechanism, the heat source-side heat exchanger, and the usage-side heat exchanger in order, and
• a heating operation state in which the refrigerant is circulated through the compression mechanism, the usage-side heat exchanger, and the heat source-side heat exchanger in order;
• an intermediate heat exchanger integrated with the heat source-side heat exchanger and using air as a heat source, the intermediate heat exchanger
• being connected to an intermediate refrigerant tube to draw refrigerant discharged from the first-stage compression element into the second-stage compression element, and
• being arranged and configured to cool the refrigerant discharged from the first-stage compression element and drawn into the second-stage compression element;
• and
• an intermediate heat exchanger bypass tube connected to the intermediate refrigerant tube so as to bypass the intermediate heat exchanger,
• the intermediate heat exchanger being disposed above the heat source-side heat exchanger, and
• the intermediate heat exchanger bypass tube being arranged and configured to ensure that refrigerant does not flow to the intermediate heat exchanger when a reverse cycle defrosting operation is performed to defrost the heat source-side heat exchanger by switching the switching mechanism to the cooling operation state.