To resolve a problem in an air conditioner wherein it is common that standard piping diameters are different due to a difference in design pressures or that a gas refrigerant flow velocity tends to drop when gas specific gravity of a new refrigerant is increased, dropping of the flow velocity occurs when an inner diameter of an existing piping to be appropriated is larger than an inner diameter of a standard piping of a new refrigerant corresponding apparatus, and particularly, since refrigerating machine oil in a gas refrigerant in a gas piping accumulates in the piping and reliability of a compressor is deteriorated, the existing piping can not be appropriated, or restrictions are provided or the like with respect to installation conditions of an indoor unit and an outdoor unit in such a case.
In the air conditioner, when changing a working refrigerant from an old refrigerant including chlorine to a new refrigerant not including chlorine, and appropriating refrigerant piping used when using the old refrigerant, a new refrigerant circuit is formed by connecting a compressor 1, an outdoor heat exchanger 3, and an indoor heat exchanger 5 by gas side extension piping and liquid side extension piping of the refrigerant piping, and a composition is provided having a means for maintaining the refrigerant flow velocity at a constant speed or more.
Tadahiko Inaba
Kanako Murakami
Nakatsuru Kazutaka