<p>A pump for a high-pressure cleaning apparatus for delivering cleaning liquid is provided. The pump has at least one pump chamber into which at least one reciprocally movable piston plunges. The pump chamber is connected via at least one inlet valve to a suction conduit and via at least one outlet valve to a pressure conduit. A bypass conduit leads from the pressure conduit to the suction conduit. A bypass valve is arranged in the bypass conduit. The valve body of the bypass valve is connected to a control member which displaces the valve body to a closed or an open position and displaces a switch plunger which is coupled to the valve body to a first or a second switch position. The valve body opens a passage upstream of the valve seat which becomes wider when the valve body is at a predetermined distance from the valve seat.</p>
