The invention relates to a valve with a housing, a valve seat and a setting member which is provided in the housing and has a seal, the sealing surface of which comes into contact with the valve seat in the closed position of the setting member, and wherein during the adjustment the valve seat is retained on the housing so as to be displaceable relative to the sealing surface. During the adjustment the valve seat is also movable in an angular range in such a way that the valve seat rests flat on the sealing surface in the closed position.