Water Motor Alarms

Water motor alarms, commonly referred to as water motor gongs, are mechanically operated audible signaling devices used to indicate the flow of water through a fire protection system. Their primary function is to provide a local, reliable alarm when a sprinkler system activates, independent of electrical power.

These devices operate by diverting a small portion of water from the alarm line of a wet pipe or other system through a piping connection to the water motor. As water flows, it drives an internal turbine or paddle wheel, which in turn actuates an external gong, producing a continuous ringing sound for the duration of water flow. This provides immediate on-site notification of system operation.

Water motor alarms are typically installed on wet pipe systems but may also be used with other system types where appropriate trim arrangements are provided. Their simplicity, durability, and independence from electrical systems make them a dependable means of alarm signaling.