Why is a check valve used in the discharge of a fire pump?

Why is a check valve used in the discharge of a fire pump?

• A. To prevent reverse flow when the pump is not running and to maintain system pressure.
• B. To increase discharge pressure beyond design.
• C. To drain water back to the source when the pump starts.
• D. To improve pump efficiency during normal operation.

Answer: (A)

The main idea is to stop water from flowing backward through a fire pump when it isn’t running and to keep the discharge side pressurized. A discharge check valve prevents reverse flow from the system back into the pump, so once the pump stops water can’t drain out of the discharge line or pull water away from the pump’s primed condition. This helps maintain immediate readiness—water remains in the downstream piping at the correct pressure for a fire event. It also reduces the risk of pressure loss in the system when other valves in the network close or open. The device doesn’t raise discharge pressure beyond what the pump and system are designed to deliver, it doesn’t drain water back to the source upon starting, and it doesn’t improve efficiency during normal operation.

The main idea is to stop water from flowing backward through a fire pump when it isn’t running and to keep the discharge side pressurized. A discharge check valve prevents reverse flow from the system back into the pump, so once the pump stops water can’t drain out of the discharge line or pull water away from the pump’s primed condition. This helps maintain immediate readiness—water remains in the downstream piping at the correct pressure for a fire event. It also reduces the risk of pressure loss in the system when other valves in the network close or open. The device doesn’t raise discharge pressure beyond what the pump and system are designed to deliver, it doesn’t drain water back to the source upon starting, and it doesn’t improve efficiency during normal operation.