In a two-pump relay, what is the purpose of keeping both pumps aligned during a discharge pressure increase?

In a two-pump relay, what is the purpose of keeping both pumps aligned during a discharge pressure increase?

• A. To prevent pressure surges, ensure consistent nozzle pressure, and avoid misalignment that could cause pump overload or dry running
• B. To maximize fuel efficiency
• C. To reduce noise and vibration
• D. To simplify maintenance schedules

Answer: (A)

The main idea here is keeping both pumps working together so the system head stays stable as discharge pressure rises. In a two-pump relay, you want both pumps to share the load and deliver similar discharge pressure and flow. If one pump comes up faster than the other or is not aligned with the same pressure, you can create a pressure surge or a drop downstream. That surge can overload a pump, cause hydraulic shock in the hose layout, or push a pump toward dry running if the water column isn’t maintained. Maintaining alignment also keeps nozzle pressure consistent. When the water leaves the nozzle at a steady pressure, firefighters can perform more predictably and safely, and the attack line remains effective. If the pumps are misaligned, one pump could be forced to work harder, increasing the risk of overheating or mechanical stress, while the other risks losing prime or starving for water. So, coordinating and keeping both pumps aligned during a discharge pressure increase minimizes surges, maintains steady nozzle pressure, and helps prevent overload or dry running in the relay.

The main idea here is keeping both pumps working together so the system head stays stable as discharge pressure rises. In a two-pump relay, you want both pumps to share the load and deliver similar discharge pressure and flow. If one pump comes up faster than the other or is not aligned with the same pressure, you can create a pressure surge or a drop downstream. That surge can overload a pump, cause hydraulic shock in the hose layout, or push a pump toward dry running if the water column isn’t maintained.

Maintaining alignment also keeps nozzle pressure consistent. When the water leaves the nozzle at a steady pressure, firefighters can perform more predictably and safely, and the attack line remains effective. If the pumps are misaligned, one pump could be forced to work harder, increasing the risk of overheating or mechanical stress, while the other risks losing prime or starving for water.

So, coordinating and keeping both pumps aligned during a discharge pressure increase minimizes surges, maintains steady nozzle pressure, and helps prevent overload or dry running in the relay.