To provide a refrigerating plant having construction using a separation membrane for separating and removing noncondensable gas residing in refrigerant communication pipes in the state that it is mixed with refrigerant in a refrigerant circuit during site construction, preventing the release of the refrigerant into the air even when the separation membrane has lower separating capability.

An air conditioning system 1 comprises a heat source unit 2 and a service unit 5 connected to each other via the refrigerant communication pipes 6, 7 to constitute the refrigerant circuit 10. Herein, a separation membrane device 34 and a refrigerant collecting mechanism 65 are provided. The separation membrane device 34 has a separation membrane 34b for circulating the refrigerant in the refrigerant circuit 10 with the operation of a compressor 21 and separating the noncondensable gas residing in the refrigerant communication pipes 6, 7 from the refrigerant flowing in a liquid side refrigerant circuit 11, and it exhausts the noncondensable gas separated by the separation membrane 34b to the outside of the refrigerant circuit 10. The refrigerant collecting mechanism 65 collects the refrigerant contained in the noncondensable gas separated by the separation membrane device 34b.