Which switch connects the sprinkler system to the fire alarm system?

The flow switch is critical in connecting the sprinkler system to the fire alarm system because it monitors the flow of water in the sprinkler pipes. When the flow of water is detected, indicating that the sprinkler system has been activated, the flow switch sends a signal to the fire alarm system. This integration is essential for alerting occupants and firefighters that the sprinkler system is engaged in fighting a fire, ensuring timely response and enhancing safety measures within the building.

The other options play different roles within fire protection systems. A pressure switch typically monitors the pressure levels in the system but does not specifically indicate whether the sprinklers are operating. A control switch may manage various functions but is not directly tied to the sprinkler flow. An alarm switch also serves a purpose in notifying individuals of a fire condition but does not connect the sprinkler system's operation with the fire alarm system in the same direct manner that the flow switch does.