REFRIGERATION/AIR-CONDITIONING DEVICE

摘要

This refrigeration/air-conditioning device (for example, a refrigerating machine 100) is equipped with: a refrigeration cycle which is configured by a variable displacement compressor 1, a condenser 2, a decompression device 3, and an evaporator 4 being connected through refrigerant pipes 20 and 21 and circulates a refrigerant therethrough; and a control device 10 which controls the operation and halting of the refrigeration cycle and the operational frequency of the compressor 1. The control device 10 performs oil recovery operation for returning the refrigeration oil accumulated in refrigerant pipe 21 to the compressor 1. The control device 10 calculates the zero penetration frequency corresponding to the pipe inner diameter of refrigerant pipe 21 from the evaporation temperature in the evaporator 4, and changes the operational frequency of the oil recovery operation so that the operational frequency of the oil recovery operation exceeds the zero penetration frequency if the operational frequency of the oil recovery operation is equal to or less than the zero penetration frequency at the evaporation temperature.