Abstract: A system for controlling the temperature of the interior of a vehicle, e.g., a railway carriage, comprising a refrigerant circuit (18) having an evaporator (21) through which air is passed to outlets (24) to the interior of the vehicle. A condenser (25) of the refrigerant circuit (18) is cooled by liquid-containing pipes which extend over the entire height of the vehicle to a liquid/air heat exchanger (19). The refrigerant unit is arranged in or on the roof of the vehicle and heat exchanger (19) is arranged on or under the floor of the vehicle, or vice versa.