| abstract |
A refrigeration apparatus capable of exhibiting a desired refrigeration capacity with a small amount of refrigerant is realized by using a single refrigerant of HFO refrigerant or a mixed refrigerant containing an HFO refrigerant. A heat exchanger (23, 27) is constituted by a microchannel heat exchanger having a microchannel serving as a refrigerant flow path. Alternatively, refrigeration oil that is incompatible or weakly compatible with the refrigerant in the refrigerant circuit (20) is used as the refrigeration oil supplied to the sliding portion of the compressor (21). Alternatively, the pressure of the oil sump space (44) for storing the refrigerating machine oil supplied to the sliding portion of the compressor (21) is set to be a low pressure of the refrigerating cycle during the refrigerating cycle. Alternatively, during the cooling operation, the refrigerant at the outlet of the heat source side heat exchanger (23) is allowed to enter a saturated liquid single-phase state or a gas-liquid two-phase state, and flows out of the heat source side heat exchanger (23). Among the refrigerants reduced to the intermediate pressure of the refrigeration cycle, the refrigerant in the saturated liquid state is supplied to the use side heat exchanger (27). [Selection] Figure 1 |