To provide a method of recycling an existing refrigerant pipe in a refrigerating cycle facility by collecting old oil in safety at low costs in changing a refrigerant from a conventional refrigerant to a different new refrigerant in the refrigerating cycle equipment, and also to provide a cleaning device for executing the recycling method of the existing refrigerant pipe.

The specific amount of the new oil is supplied into the refrigerating cycle equipment 1 by a new oil supplying portion 21, then an outdoor unit 3 after the change is operated to accumulate the specific amount of the oil in the refrigerating cycle equipment 1 in an oil collecting portion 25, and the accumulated oil is collected.