What are the different pump mechanisms?
A. Surface pumps are often centrifugal pumps. The motor spins an impeller which pulls water in and forces it out with a centrifugal force. The water in captured in the front housing and sent out the pipe fitting of the outlet. Submersible pumps are piston pumps. The piston goes in and out of the cylinder pushing and pulling water in both directions. The water comes from the pump in pulses. These pumps work with positive displacement. The water is trapped and forced by a sealed cavity against pressure. Even when moving slowly in cloudy weather, the pump will still force water uphill. A centrifugal pump needs to move at least 6 gallons per minute to move water uphill.
