AIR CONDITIONER

PURPOSE:To prevent a concentration of oxygen from being decreased and to prevent a concentration of toxic gas component from being increased by a method wherein indoor air is separated into oxygen and other gaseous substances by the first gas separating device, surrounding air is separated into oxygen and other gaseous substances by the second gas separator and the gaseous substances except separated oxygen are discharged into surrounding atmosphere. CONSTITUTION:A supplying pipe 9A for returning oxygen separated by the first gas separating device 6A into a room 5 and a supplying pipe 9B for supplementing oxygen separated by the second separating device 6B into the room 5 are passed together with a refrigerant pipe 3 through a hole 21 formed in a wall 4, and their extremity end openings are opened into an air passage within an indoor device 1. The first gas separating device 6A continuously separates indoor air into oxygen and other gaseous substances, returns the separated oxygen into the room and at the same time other gaseous substances except oxygen are discharged out of the room. The second separating device 6b and the first gas separating device 6A continuously separate the surrounding air into oxygen and other gaseous substances except oxygen and the separated oxygen is supplemented into the room 5.