Description: The disc check valve boiler feed check valve is designed specifically for use on boiler feedwater systems. It is a stainless steel disc check valve with a soft EPDM seat to ensure tight shut-off against boiler pressure, even under poor water conditions. The disc check valve is normally installed between flanges in the boiler feed water line. Cast-in lugs on the valve body allow the valve to be centralised easily.
Note: The disc check valve is similar in specification and appearance, but has a slightly different seat design. We recommend only the disc check valve for boiler feedwater applications.
Standards: Designed and manufactured in accordance with BS 7438.
Standard shut-off: Shut-off standard meets DIN 3230 part 3 BN1 and BO1 providing a differential pressure exists.
Certification: This product is available with certification to EN 10204 2.2.
Note: all certification/inspection requirements must be stated at the time of order placement.
WARNING: The disc check valve must not be used on any fluids categorised as Group 1 according to the E.C. directive on the classification of dangerous substances, e.g. explosive, flammable, toxic and oxidising substances.
Sizes and pipe connections: DN20, DN25, DN32, DN40 and DN50. The valves are selected to suit the feedwater line size and are suitable for installation between the following flanges:- EN 1092 PN6, 10, 16, 25, 40 and BS 10 Table D, E, F, and H.

Operation: The disc check valve is opened by the boiler feedwater pressure and is closed by its spring as soon as the flow ceases, preventing reverse flow. The strong spring supports the head of water in an elevated feedtank when there is no pressure in the boiler, preventing the boiler flooding. A vacuum breaker is recommended on the boiler to prevent the valve being drawn off its seat as the boiler cools.