To provide a refrigerating air-conditioner capable of replacing easily a heat source side unit and a load side unit, without requiring a wide installation space, while diverting existing piping, and a renewal method therefor.

This refrigerating air conditioner is provided with the heat source side unit 1 including a circuit connected with at least an accumulator, a compressor and a heat source side heat exchanger in order, and a return oil circuit 12 for returning a refrigerator oil from the accumulator 5 to the compressor 6, the load side unit including the first contraction device and a load side heat exchanger 2, the first extension piping for connecting the heat source side heat-exchanger to the first contraction device, and the second extension piping for connecting the load side heat exchanger to the compressor. The refrigerating air conditioner is further provided with a discharge port provided in the accumulator, and for discharging the foreign matter in the accumulator after a cleaning operation, and an oil returning circuit opening and closing means provided in the oil returning circuit, for opening the oil returning circuit to return the refrigerator oil to the compressor a prescribed amount by a prescribed amount in a usual operation, and for closing the oil returning circuit in the cleaning operation.