A refrigerating system for air-conditioning an air-conditioned area, and incorporating therein a variable capacity refrigerant compressor in which the delivery amount of the compressed refrigerant is varied by changing the stroke of the reciprocating pistons which are operatively connected to a swash plate mechanism by changing its angle of inclination in response to a change in the pressure in a crank chamber, a condenser for condensing the compressed gas-phase refrigerant from the compressor, a pressure reducing unit for reducing the pressure of the liquid-phase refrigerant, an evaporator for vaporizing the liquid-phase refrigerant by removing heat from the air, around the evaporator, which cools the air-conditioned area, and a refrigerant supply conduit supplying the crank chamber of the compressor with a part of the liquid-phase refrigerant flowing in a portion of the refrigerant conduit extending from the condenser to the evaporator so that during the minimum capacity operation of the compressor, the compressor is cooled and lubricated by the supplied refrigerant. A flow regulating unit for adjustably regulating the flow of the liquid-phase refrigerant flowing through the refrigerant supply conduit is also arranged.