A flushing device comprising an evacuation fitting (6) that is provided with a sealing member (7) within a pressurized container (2). The sealing member (7) is lifted counter to the pressure of a piston (16) in order to initiate the flushing process. A connecting device (39) for a water pipe (24) is disposed on the container (2). The flushing device further comprises a structure (49, 50) for flushing with a partial quantity of the flushing water. For example, the structure (49, 50) is provided with a power-loaded part (50) which moves the valve member (7) down onto the valve seat (5) of the evacuation fitting (6) when the flushing process is interrupted. In an alternative embodiment, two chambers are provided, only one of which is emptied during partial flushing. Flushing water can be conserved by the fact that the flushing process can be interrupted.