An Alarm Check Valve Assembly (ACVA) is a key component of a fire sprinkler system. It is designed to control the flow of water into the sprinkler system while also providing an alarm signal in case of water flow. The ACVA is typically installed on the main water supply line to the sprinkler system.

Here’s a breakdown of the components and functions of an Alarm Check Valve Assembly:

1. Check Valve: The check valve is a crucial part of the assembly. It allows water to flow in one direction only, preventing backflow or reverse flow from the sprinkler system back into the water supply. This ensures that water is available to the sprinklers when needed.
2. Alarm Pressure Switch: The ACVA includes an alarm pressure switch that is sensitive to changes in water pressure within the system. When water flows through the check valve and reaches a predetermined pressure, the switch activates, sending an electrical signal to an alarm panel or a monitoring system. This signal alerts occupants or monitoring personnel to the presence of flowing water, indicating a potential fire event.
3. Alarm Test Connection: The ACVA typically has a test connection point. It allows for periodic testing and maintenance of the alarm pressure switch and associated alarm system. By connecting a test device or gauge to this point, technicians can verify the proper functioning of the alarm system.
4. Waterflow Alarm: The ACVA is connected to an alarm system that can audibly and visually indicate the activation of a sprinkler system due to water flow. This alarm helps to alert occupants and emergency responders to the presence of a fire and the activation of the sprinkler system.
5. Water Supply Control: The ACVA also serves as a control valve for the water supply to the sprinkler system. In the event of a fire, when one or more sprinklers open and water flows through the system, the ACVA opens fully, allowing water to flow freely and extinguish the fire.