Abstract: A motor vehicle heat exchanger system with a closed circuit for an operating medium includes an evaporator for evaporating the operating medium and a condenser for condensing the vaporous operating medium AM is provided. A reservoir for the liquid operating medium is integrated between the condense and the evaporator. Liquid operating medium is conducted from the reservoir via a feed line into the evaporator. In addition the reservoir and the evaporator are connected with each other via a compensation line. Vapor which may form during operation of the motor vehicle heat exchanger system on the liquid side of the evaporator can escape through the compensation line thereby achieving a pressure compensation.