How do you adjust a pump to compensate for a low intake pressure during drafting?

• A. Increase discharge pressure to achieve the required nozzle pressure and consider additional intake lines or alternate water sources if needed.
• B. Decrease discharge pressure to reduce load.
• C. Increase water temperature.
• D. Stop pumping until intake improves.

Answer: (A)

When drafting, you must ensure the nozzle receives the required pressure even if the suction is weak. Low intake pressure cuts into the pump’s ability to deliver the target nozzle pressure, so you compensate by raising the pump’s discharge pressure to make up the difference. Do this within what the pump and hoses can safely handle, taking into account friction losses in the hose layout and fittings. If the intake remains insufficient, you can improve the suction by adding another intake line or using an alternate water source to lift the available head. Lowering discharge pressure would reduce nozzle pressure and won’t meet firefighting needs, while increasing water temperature or stopping pumping don’t address the suction deficit.