Abstract: An air conditioner for a vehicle has a housing (1) accommodating an evaporator (2) and a heater (3) which are connected to a compressor and to an engine cooling system, respectively, and a fan (7) and controlled gates (9, 13) of hot and cool air ducts (8, 12). The evaporator 2 and heater (3) are in the form of a stack of alternating heat exchange plates having passages 4, 5 for a heat carrier. An auxiliary controlled gate (14) of the hot air duct (8) is provided between the fan (7) and the stack of the heat exchange plates for movement between two positions. The gate shuts off a part of the surface of the stack of the heat exchange plates in the first position, and in the second position, the gate uncovers the entire surface of the stack of the heat exchange plates. The invention may be used in self-propelled vehicles.