PURPOSE: To provide an air conditioning facility which can form a comfortable air conditioned space without deviating the distribution of the conditioned air in a large space room having a high ceiling and a wide floor surface and has energy conservation.

CONSTITUTION: A plurality of diffusing posts 28 and a plurality of suction posts 30 are stood on the floor in a large space room 10. The conditioned airs are diffused from air outlets 26 formed at the upper side faces of the posts 28, and the return air is sucked from the suction ports 29 formed at the lower side faces of the posts 30. Thus, the installing places of the posts 28 and 30 can be freely laid out. The heights of the outlets 26 can be freely set by altering the heights of the diffusing posts 28. Thus, since only the residence space where person live can be air conditioned without air conditioning the vicinity of the ceiling of the non-dwelling space in the large space room, the energy conservation can be obtained.