DELUGE SYSTEM WET PILOT ACTUATION

A deluge fire protection system with wet pilot actuation uses a hydraulic detection line filled with water to control the opening of the main deluge valve. These systems incorporate all open sprinklers or nozzles connected to the system piping. The system’s main valve remains closed by water pressure in its diaphragm chamber, sometimes referred to as a pressure or control chamber. A separate wet pilot line, connected to the pressure chamber, contains heat-sensitive pilot sprinklers or thermostatic release devices. When exposed to fire, one or more pilot sprinklers fuses open, releasing water from the pilot line. This drop in pressure, vents the pressure chamber and releases the main valve clapper or diaphragm seal. As a result, water floods the system piping and discharges simultaneously through all open spray nozzles or deluge heads. The wet pilot line therefore serves as both the detection and control mechanism, providing a reliable, hydraulically operated means of automatic system activation without the need for electrical components.