Abstract: The present invention relates to a device for controlling the flow of a fluid in a compartment (4) with an inlet opening (5) and an outlet opening (6). The device comprises an inlet channel (8) connected to the inlet opening for transportation of fluid to the compartment, an outlet channel (9) connected to the outlet opening for transportation of fluid from the compartment and a pump (17) arranged to pump the fluid. The compartment is provided with a third opening (12). The device comprises a distribution chamber (15) connected to the inlet channel and a third channel (14) connected between the distribution chamber and the third opening for transportation of fluid between the distribution chamber and the compartment.