To provide a refrigerating cycle device constructed for replacement with trouble-free refrigerant in environmental protection and its cleaning operation method for replacing refrigerant.

The refrigerating cycle device comprises a refrigerant circuit consisting of a compressor, a heat source machine side heat exchanger, a flow control means and a service side heat exchanger connected together in sequence, a first connection pipe for connecting the heat source machine side heat exchanger to one end of the flow control means, a second connection pipe for connecting the other end of the service side heat exchanger to the compressor, and a cleaning means having one end connected to the first connection pipe and the other end connected to the second connection pipe. Herein, the cleaning means is connected thereto for cleaning operation when replacing old refrigerant with fresh refrigerant. The cleaning means is divided into a separate type cleaning machine consisting of an oil separator and a foreign matter trapping means and other components, and the separate type cleaning machine is detachable from the cleaning means.