The 3 main factors that influence discharge pressure are:

• A. Amount of water being discharged; Speed of impeller; Incoming water pressure
• B. Area of discharge valve; Temperature; Ambient pressure
• C. Pipe diameter; Length of hose; Friction loss
• D. Ambient humidity; Seat height; Water clarity

Answer: (A)

Discharge pressure is shaped by the energy you put into the water and the pressure available at the pump’s inlet. The three main factors you control are: how much water you’re pushing (the flow rate), how fast the pump is turning (impeller speed), and the pressure coming into the pump (incoming water pressure). If you increase the flow, friction losses in hoses and fittings rise, which can change the pressure you need to maintain the same discharge. Turning the pump faster increases the energy added to each unit of water, raising the discharge pressure. A higher inlet pressure adds to the overall pressure the pump can deliver into the system. The other items listed affect pressure indirectly or aren’t primary controls of discharge pressure in typical pump operations.