Valve actuator system

Sanitary valve system comprising:

• a valve in a valve housing with at least one inlet and at least one outlet, which valve is a sanitary valve with at least one surface formed of a hygienic material that prevents growth of bacteria or fungus and configured to control a flow from the at least one inlet to the at least one outlet by means of a valve regulating element that is mechanically connected to a valve actuator having an actuator housing in which at least one piston separates the actuator housing into a first chamber and a second chamber, the piston being movable by an incompressible liquid medium comprised primarily of water in the first and second chambers, wherein the liquid medium is regulated in the first chamber via a first line and in the second chamber via a second line by an electromagnetically activated regulator that is configured to regulate pressure or flow of the liquid medium in the first and second lines to position the sanitary valve and to block the first and second lines to lock the position of the sanitary valve.