FIELD: air-conditioning systems for habitable spaces. SUBSTANCE: air-conditioning unit includes heat-transfer device 4 for preliminary heating of supply air by transfer of heat from used air, heating means including heat source 11 for further heating of supply air, cooling means including cooling source 14 for cooling supply air and control devices 16, 17, 18, 21, 32, 33 and 34 for measuring temperature of supply air and control of heat-transfer device, heating and cooling means on basis of measured temperature. To simplify construction of unit, heating source 11 and cooling source 14 are connected with heat-transfer device 4, thus performing preliminary heating, further heating and cooling of supply air in one heat-transfer device. EFFECT: simplified construction. 7 cl, 5 dwg
