Air-conditioning system for a vehicle, having a refrigerant circuit through which a refrigerant can flow and which is formed as a heat-pump circuit and a refrigeration-system circuit and having, assigned to said refrigerant circuit, a compressor, at least one exterior heat exchanger, at least one interior heat exchanger which is assigned an interior heating condenser, wherein a device for generating an air flow which can be thermally coupled to the interior heat exchanger and to the interior heating condenser is provided, and a dosing device is provided, by means of which a throughflow of the interior heating condenser with at least a partial flow of the thermally coupled air flow can be metered, wherein - in a heat pump mode, the refrigerant can be or is conveyed from the high-pressure side of the compressor into the interior heating condenser, can be or is conveyed from the interior heating condenser through a first expansion valve to the interior heat exchanger, can be or is conveyed from the interior heat exchanger through an expansion valve, which can be flowed through in both directions, to the exterior heat exchanger, can be or is conveyed from the exterior heat exchanger to the low-pressure side of the compressor, and - in a refrigeration system mode, the refrigerant can be or is conveyed from the high-pressure side of the compressor into the interior heating condenser, can be or is conveyed, bypassing the first expansion valve, from the interior heating condenser to the exterior heat exchanger, can be conveyed from the exterior heat exchanger through the expansion valve, which can be flowed through in both directions, to the interior heat exchanger, from the interior heat exchanger to the low-pressure side of the compressor, characterized in that the refrigerant circuit is assigned an exhaust-air heat exchanger which can be flowed through by refrigerant and via which an air flow from a vehicle interior compartment can be or is conducted into an exterior space, and the exhaust-air heat exchanger, in a heat pump mode, operates as an evaporator and, in a refrigeration system mode, operates as a condenser or gas cooler. - in a heat pump mode, the refrigerant can be or is conveyed from the high-pressure side of the compressor into the interior heating condenser, can be or is conveyed from the interior heating condenser through a first expansion valve to the interior heat exchanger, can be or is conveyed from the interior heat exchanger through an expansion valve, which can be flowed through in both directions, to the exterior heat exchanger, can be or is conveyed from the exterior heat exchanger to the low-pressure side of the compressor, and - in a refrigeration system mode, the refrigerant can be or is conveyed from the high-pressure side of the compressor into the interior heating condenser, can be or is conveyed, bypassing the first expansion valve, from the interior heating condenser to the exterior heat exchanger, can be conveyed from the exterior heat exchanger through the expansion valve, which can be flowed through in both directions, to the interior heat exchanger, from the interior heat exchanger to the low-pressure side of the compressor,