Check Valves

A fire protection check valve is a one-way valve designed to allow water flow in the forward direction while preventing reverse flow that could compromise system reliability or contaminate the water supply. These valves are critical in ensuring sprinkler systems remain primed, water supplies remain protected, and system pressure is maintained. Several styles exist, each serving specific applications.

Swing check valves operate with a hinged disc that swings open under forward flow and closes by gravity or back pressure, making them common in larger piping systems. Wafer check valves, by contrast, are compact, lightweight designs that fit between flanges; they often use a spring-loaded disc for rapid closure, reducing the risk of water hammer. Riser check valves, specifically used in sprinkler risers, are typically UL/FM listed and designed for vertical installation with trim for testing and draining. Backflow preventers, while technically specialized check assemblies, include two or more check valves with additional relief and shutoff features, ensuring no backflow from fire systems into potable water supplies.

Each style balances function, space, and code requirements, but collectively, check valves are indispensable to maintaining the integrity and reliability of automatic fire protection systems.