What part of a fire sprinkler system helps in controlling water flow?

The alarm check valve is a critical component in a fire sprinkler system that helps control water flow to the various sprinkler heads. Its primary function is to monitor the water flow and pressure within the system. When there is a fire, the alarm check valve allows water to flow into the sprinkler system, activating the sprinklers in the affected areas.

By maintaining the appropriate pressure and ensuring that the system only activates when necessary, the alarm check valve plays a vital role in the overall efficiency and effectiveness of the fire protection system. It also helps to prevent water from flowing backward into the water supply, protecting the integrity of both the fire sprinkler system and the municipal water supply.

In contrast, the other components mentioned, such as the fire department connection, hydraulic name plates, and main drain, serve different purposes. The fire department connection is where firefighters can connect their hoses to boost the water supply; hydraulic name plates provide essential information about the system's design and flow rates; and the main drain is used for testing and maintenance of the system. Each has a specific function, but it is the alarm check valve that directly controls the flow of water to the sprinklers themselves.