| 摘要 |
A refrigeration and freezer unit Al comprises a compressor 1 for circulating a refrigerant, as well as an oil separator 2 connected to the pressure pipe of the compressor, via which oil separator the refrigerant flows to a compressed gas heat exchanger 4 which forms part of the refrigeration and freezer unit, which compressed gas heat exchanger 4 is connected via a vapour return pipe LI to a cascade heat exchanger 28 from which a condensate pipe L2 carries the liquid to an evaporator 11 which forms part of the refrigeration and freezer unit, which evaporator leads the refrigerant to a suction pipe of the compressor 1. The refrigerant is C02 and between the oil separator, the compressed gas heat exchanger, the evaporator and the compressor is located a reversing valve 3 which in a first operation state connects the oil separator to the compressed gas heat exchanger and the evaporator to the compressor, and in a second operation state connects the oil separator to the evaporator and the compressed gas heat exchanger to the compressor. |
