Dry Pilot (Pneumatic) Actuators

Dry pilot (pneumatic) actuators are mechanical devices used in fire protection systems to control the release of deluge, preaction, and some dry pipe valves through air pressure. Their primary function is to maintain a pressurized air or nitrogen signal in a pilot line; when heat-operated devices (such as pilot sprinklers or pneumatic detectors) open, the resulting pressure loss causes the actuator to trip open, releasing the priming pressure and allowing the main valve to open.

Two common types are standard pressure actuators and low-pressure actuators. Standard pressure actuators require higher air pressure within the system piping than Low Pressure Actuators. Low-pressure actuators allow for lower air pressure to be maintained within the system piping. This can minimize compressor demands.

These actuators are widely used in preaction systems as part of a pneumatic detection or release trim, often serving as an independent or backup release method. In certain dry pipe systems, pneumatic actuators are used to assist in valve operation.  These actuators allow for non-electrical actuation in specialized applications.