Patent ID: 8356490

Claim:
A refrigeration apparatus using a refrigerant operating in a supercritical range, the refrigeration apparatus comprising: a compression mechanism having a plurality of compression elements including a first-stage compression element and a second-stage compression element, the compression mechanism being configured and arranged to sequentially compress refrigerant in the first-stage compression element and then in the second-stage compression element; a heat source-side heat exchanger with air being used as a heat source to cool or heat the refrigerant; an expansion mechanism configured and arranged to depressurize the refrigerant; a usage-side heat exchanger configured and arranged to function as a heater or cooler of refrigerant; a switching mechanism configured and arranged to switch between a cooling operation state sequentially circulating the refrigerant through the compression mechanism, the heat source-side heat exchanger, the expansion mechanism, and the usage-side heat exchanger, and a heating operation state sequentially circulating the refrigerant through the compression mechanism, the usage-side heat exchanger, the expansion mechanism, and the heat source-side heat exchanger; an intercooler integrated with the heat source-side heat exchanger and having air as a heat source, the intercooler being configured and arranged to cool refrigerant flowing through an intermediate refrigerant tube, the intermediate refrigerant tube drawing refrigerant discharged from the first-stage compression element into the second-stage compression element; and an intercooler bypass tube connected to the intermediate refrigerant tube and arranged to bypass the intercooler, the refrigerant being caused to flow to the heat source-side heat exchanger and the intercooler upon the heat source-side heat exchanger being caused to function as a cooler of refrigerant and a defrosting operation for defrosting the heat source-side heat exchanger being performed, and the intercooler bypass tube ensuring the refrigerant does not flow to the intercooler upon the heat source-side heat exchanger being caused to function as a cooler of refrigerant and after defrosting of the intercooler is detected as being complete.