PURPOSE: To perform an effective recovery of waste heat and enable the air conditioner to be corresponded to an intake and discharging port arranged at an outer wall by a method wherein the discharged air of indoor part is thermally recovered by a total heat exchanger and means for reusing it by an outdoor heat exchanger of an outdoor unit through a chamber is arranged.

CONSTITUTION: A total heat exchanger 19 has an indoor discharging port 29 to be sucked for discharging the partial air in the interior to be cooled or heated below a front panel 30 and a top plate 32 is provided with a room dis charging port 31 for blowing the surrounding air into the room through the full heat exchanger. The partial air which is conditioned is discharged through the total heat exchanger 19, a part of the surrounding atmosphere is fed, the waste heat of the indoor air is recovered to the surrounding atmosphere by the total heat exchanger 33 and blown out into the room, the discharged air is further passed to the outdoor heat exchanger 26 and the not-recovered heat is reused to a double effect.