AIR CONDITIONER

PURPOSE:To simplify the switching mechanism in the operation mode, reducing the parts required in number and cutting down the work steps in the assembly procedure, by providing a damper-switching device designed to switch by means of a set of dampers between passageways for outside air and discharged air to an all-purpose heat exchanger and passageways bypassing the all-purpose heat exchanger. CONSTITUTION:When the operation is in the mode for recovering the waste heat, a switching damper 7 takes a position (a); indoor air A1 drawn in by a return-air fan 1 is divided into air-for-discharge C1 and air for circulation by the opening-closing action of a return-air damper 2; after passing the return-air damper 2 the air for circulation is mixed with air-from-the-outdoors, D1, cleared of dust by a filter 3, undergoes heating against cooling by a cold-hot water coil 4, and is sent into the indoor space by an air-feed fan 5; both the air-for-discharge C1 and the air-from-the- outdoors D1 are drawn into an all-purpose heat exchanger 6 so that the heat is recovered from the air-for-discharge C1. When the operation is in the mode of outdoor- air cooling, the switching damper 7 takes a position (b); indoor air A1 is discharged directly without being passed through the all-purpose heat exchanger 6; air-from-the- outdoors D1 is conveyed directly to a filter 3 without being passed through the all- purpose heat exchanger 6.