Rapidrop Model C Alarm Check Valve 3 Inch

The Rapidrop Model C is a heavy-duty waterflow alarm check valve designed as the core control component in permanent wet pipe automatic fire sprinkler installations. Constructed with a high-strength ductile iron body, this 3-inch (DN80) valve features an advanced double-seated clapper assembly paired with an annular grooved seat design. When a fire sprinkler head activates, the resulting water movement forces the clapper open, allowing water to flow continuously into the system and simultaneously diverting a portion of the flow into the alarm port.

To eliminate costly false alarms caused by transient municipal water pressure spikes and surges, the Model C includes an external bypass line and can be outfitted with a specialized retard chamber. This configuration makes it highly versatile for systems under both constant and variable supply pressures. When the clapper opens fully, it drives water to actuate mechanical water motor gongs and electrical pressure switches, transmitting a rapid alarm signal to the building’s master fire panel.