OPW 199ASV Anti-Siphon Valve

The OPW 199ASV Anti-Siphon Valve is designed to help prevent siphoning of an aboveground storage tank should a leak or break occur in the fuel-supply line. The 199ASV installs on the top of an aboveground storage tank with a suction rod on the inlet and the fuel-supply line (to a remote pump) on the outlet of the valve.

A poppet in the valve remains normally closed, isolating the tank from siphoning. When the remote pump is activated, it overcomes a factory-adjusted spring set to a predetermined hydrostatic head pressure and allows flow of fuel out of the AST. An internal pressure relief valve helps absorb thermal expansion in the fuel-supply line. The 199ASV is available in female NPT threads with four different factory-adjusted hydrostatic head-pressure settings.