Taco 329-3 1/2" Sweat X 1/2" IPS Cast Iron Pressure Reducing Valve Features Include: Adjustable from 10 - 25 PSI. Built-in Check-Prevents emptying system in incoming pressure fails. Has Fast Fill Lever Exclusive Lockable Fast-Fill Lever Max Inlet Pressure: 100 PSI Max Temperature (F): 212°F Max Purpose To automatically feed water to a system whenever pressure in the system drops below the pressure setting of the valve. The Dual Control combines the Boiler Feed Valve with an in-line Pressure Relief Valve connected at the outlet end.