Series 911, 911S Combination Fill Valve and Backflow Preventers are for use in commercial and residential hydronic heating systems to provide make-up water to the boiler and prevent backflow when supply pressure falls below system pressure. It consists of a brass Watts Model 9D backflow preventer and a bronze Watts Model 1156F feed water pressure regulator in one pre-assembled unit. Model 911 has union NPT x NPT connections. Model 911S has union solder x NPT connections. The Series 911, 911S has a high capacity fill valve that provides quick system filling and purging. It is designed for use in the boiler feed lines of hydronic heating systems. Maximum Pressure: 100psi (6.9 bar).

Features

For use in hydronic heating systems boiler feed lines to provide make up water and prevent backflow

High capacity fill valve for quick system filling and purging

Union NPT x NPT or union solder x NPT connections

Designed for ease of installation and servicing