Patent ID: 6910345

Claim:
An air-conditioning unit ( 10 ) for a motor vehicle with a heating heat transfer unit ( 28 ) connected to a coolant circuit ( 42 ) of an internal combustion engine and comprising an evaporator ( 22 ) installed upstream as viewed in the direction of flow of a fan ( 36 ), whereby a compressor ( 12 ) in a refrigerant circuit ( 32 ) pumps 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, and whereby a coupled heat exchanger ( 30 ) is provided between the coolant circuit ( 42 ) and the refrigerant circuit ( 32 ), wherein the coupled heat exchanger ( 30 ) is located in the refrigerant circuit ( 32 ) on the pressure side of the compressor ( 12 ), 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 one switching valve ( 48 , 50 ) each located at 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.