Wednesday, February 01, 2012

Pressure-Reducing Fill Valves

Under ideal circumstances, closed-loop hydronic heating systems should use the same water year after year. Any oxygen present turns into iron oxide as soon as it reacts with ferrous metals in the system. Once this occurs, the oxygen can no longer cause these metals to rust. Minimal loss of water is normal, and it occurs in valves, pumps, and air vents. To offset these losses over time, systems should be equipped with a pressure reducing fill valve. When the valve senses a drop in system pressure, it restores the pressure with small amounts of fresh water from a connected supply line. A backflow preventer must be installed in conjunction with the valve to stop heating water from re-entering the potable water supply. For more heating supplies and helpful tips, visit