Self-priming centrifugal pumps use suction lift to draw liquids from a source located below the pump's inlet. Before first use, these pumps must be primed to ensure a proper seal. Self-priming trash pumps handle liquids that contain larger solids or debris. Self-priming sprinkler pumps achieve pressure and flow rates necessary for irrigation, sprinkler systems, and dewatering. Self-priming pedestal pumps do not include a motor and can be directly driven by a pulley or belt. These pumps are sized by motor horsepower to meet head and flow rate performance requirements. Impellers rotate within the pump and use centrifugal force to move liquids through the system. Seal kits and gaskets prevent water from exiting the pump body, keeping the pump motor and bearing assemblies dry. Motors power the pump to move liquids through the system. Replacement parts must match the pump's brand, series, and manufacturer model number. Check valves ensure that water flows in one direction, preventing backflow. Backflow occurs when liquid pressure changes, stops, or reverses.