Backflow Preventers & Hydraulic Control Valves

A standard check valve prevents reverse flow mechanically but is not tested for leakage and has no intermediate drain. A backflow preventer such as the HS41X combines two independent checks with an automatic intermediate drain chamber, is testable in place, and meets cross-connection control requirements for potable water protection. Check valves alone are not accepted at potable cross-connections.

On the fire service connection to the potable main, upstream of the fire pump suction or system riser. It must be accessible for testing, protected from freezing, and its head loss included in the fire pump hydraulic calculation. For high-rise systems, confirm the device rating matches the maximum static pressure of the supply.

Most hydraulic control valves — the 500X pressure reducing valve, F745X level control valve and HS41X backflow preventer — are fully self-operated by pipeline pressure and require no external power. Solenoid-controlled models such as the GKZF-1 use AC220V or DC24V for remote automation.

For drinking water networks, the HS41X backflow preventer uses a ductile iron body with EPDM seals and stainless steel 304 internals, compliant with GB/T17219 sanitary requirements. Confirm the sanitary certificate for your market — our engineers provide the documentation package with the order.

Yes. We manufacture backflow preventers, pressure reducing valves, level control valves, solenoid control valves, vortex preventers and Y-strainers and ship them as a coordinated package — matched pressure classes, trims and test reports from a single factory.