A relief valve is provided for draining water from the main supply hose and a backflow preventor valve is provided for preventing back-siphonage into the water supply. A pressure actuated warning alert system is provided to indicated venting failure....
BACKFLOW PREVENTER VALVE ASSEMBLY Two series-related check valves are separated by a chamber (the zone ) adapted to be drained by a relief valve in order to insure against backflow of water through the check valve which is nearest the water main. The relief valve incorp... ZIEG C,YELICH W...
A relief valve is provided for draining water from the main supply hose and a backflow preventor valve is provided for preventing back-siphonage into the water supply.Noelke, Michael A.
Located between the two check valves is an automatically operating pressure differential relief valve. With backflow prevention devices, it is very important to know whether the mechanism is functioning properly. Since there is no visible ... D Arnold - 《Supply House Times》 被引量: 0发表: 200...