The present invention is a piston valve device (25) for use in connection with the fire protection industry, and including features for protecting against corrosion. The corrosion protection features include a replaceable sacrificial zinc anode (8) for detecting the presence of corrosion within the piston valve device (25), a grease fitting (22) for injecting grease or lubricant material between a valve spindle (9) for moving a piston member (4) between open and closed positions, and a valve body (1) or bushing elements (14, 16) to protect against corrosion. The piston valve member (4) is made of polymeric material to protect against corrosion.