Air-conditioning unit with additional heat transfer unit in the refrigerant circuit

Abstract

The invention relates to an air-conditioning unit (10) for a motor vehicle with a heating heat transfer unit (28) connected to a coolant circuit (42) in an internal combustion engine and comprising an evaporator (22) installed upstream in the direction of flow of a fan (36). A compressor (12) in a refrigerant circuit (32) pumps a refrigerant through a gas cooler (16) and an expansion valve (20) during a cooling operation, and pumps said refrigerant to the evaporator (22) via the expansion valve (20) by by-passing the gas cooler (16) during a heating operation. A coupled heat exchanger (30) is provided between the coolant circuit (42) and the refrigerant circuit (32). The invention provides that the coupled heat exchanger (30) is located in the refrigerant circuit (32) on the pressure side of the compressor (12) upstream of the gas cooler (16), a first by-pass line (80) is provided parallel to the gas cooler (16) and the flow through the gas cooler (16) and the first by-pass line (80) is controlled by a switching valve (52) in the first by-pass line (80) and a switching valve (48, 50) located at each of the inlet and outlet of the gas cooler (16), depending on operating parameters, and a heat transfer unit (14) for a medium in a unit in the refrigerant circuit (32) is connected behind an expansion valve (20 or 38) and serves as heat source in heating operation.

Dependencies are inferred from the claim text.