A modular air-conditioning device for a motor vehicle, preferably for an electrically driven motor vehicle, comprising: a) at least two air-conditioning modules (10a, 10b), which respectively comprise a refrigerant circuit (1a, 1b) with the following components: - a, preferably electrically driven, compressor; - a first heat exchanger (W 1) for heat exchange with the space outside the vehicle and/or a component of an electric drive; - a first throttling device; - a second heat exchanger (W 2) for heat exchange with the space inside the vehicle and/or a component of an electric drive; and - a valve device, comprising a plurality of valves (5 a -5 d), for controlling a refrigerant flow within the refrigerant circuit (1a, 1b), by means of which the first heat exchanger (W 1) can be switched in a first operating mode M 1, preferably for cooling the space inside the vehicle, upstream and in a second operating mode M 2, preferably for heating the space inside the vehicle, downstream of the second heat exchanger (W 2) in the refrigerant circuit (1a, 1b); and wherein the air-conditioning modules (10a, 10b) respectively comprise a module control device (2a, 2b) for the respective activation of the valve device and/or the compressor; b) a central control device, which is designed to establish a number of active air-conditioning modules (10a, 10b) on the basis of at least one monitored operating condition and to establish whether an active air-conditioning module (10a, 10b) is operated in the first or second operating mode M 1 or M 2. a) at least two air-conditioning modules (10a, 10b), which respectively comprise a refrigerant circuit (1a, 1b) with the following components: - a, preferably electrically driven, compressor; - a first heat exchanger (W 1) for heat exchange with the space outside the vehicle and/or a component of an electric drive; - a first throttling device; - a second heat exchanger (W 2) for heat exchange with the space inside the vehicle and/or a component of an electric drive; and - a valve device, comprising a plurality of valves (5 a -5 d), for controlling a refrigerant flow within the refrigerant circuit (1a, 1b), by means of which the first heat exchanger (W 1) can be switched in a first operating mode M 1, preferably for cooling the space inside the vehicle, upstream and in a second operating mode M 2, preferably for heating the space inside the vehicle, downstream of the second heat exchanger (W 2) in the refrigerant circuit (1a, 1b); and wherein the air-conditioning modules (10a, 10b) respectively comprise a module control device (2a, 2b) for the respective activation of the valve device and/or the compressor; - a, preferably electrically driven, compressor; - a first heat exchanger (W 1) for heat exchange with the space outside the vehicle and/or a component of an electric drive; - a first throttling device; - a second heat exchanger (W 2) for heat exchange with the space inside the vehicle and/or a component of an electric drive; and - a valve device, comprising a plurality of valves (5 a -5 d), for controlling a refrigerant flow within the refrigerant circuit (1a, 1b), by means of which the first heat exchanger (W 1) can be switched in a first operating mode M 1, preferably for cooling the space inside the vehicle, upstream and in a second operating mode M 2, preferably for heating the space inside the vehicle, downstream of the second heat exchanger (W 2) in the refrigerant circuit (1a, 1b); b) a central control device, which is designed to establish a number of active air-conditioning modules (10a, 10b) on the basis of at least one monitored operating condition and to establish whether an active air-conditioning module (10a, 10b) is operated in the first or second operating mode M 1 or M 2.