The Delta Digital Auto Blowdown Valve creates an effective steam environment. This add-on to the 5COM Series Steam Generators automatically relieves trapped pressure at the end of your final use. Emptying the generator ensures quality and maximizes its life. Blowdown for boilers cannot be ordered standalone, they must be ordered with a boiler. Automatically empties the steam generator at the end of each day Requires a 5COM Series Steam Generator US Customer Support and Service Installation and Operation Manual Drain Outlet Connection : 1" Pipe