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Troubleshooting of Low Flow & No Water Discharge for YW Sewage Pump

July 3, 2026 2 min read Haquan
Troubleshooting of Low Flow & No Water Discharge for YW Sewage Pump

Insufficient flow or zero water output is the most common fault of YW Liquid-Submerged Sewage Pump during operation, we sort out fault causes and targeted solutions:
(1)Impeller Blocked by Fiber & Solid Debris
Cause: Long fiber or large solid particles stuck in single channel impeller flow channel.
Solution: Dismantle pump body, clean all sundries inside impeller and volute.
(2)Sealing Ring Serious Wear
Cause: Long-term abrasion of solid particles leads to large internal clearance, liquid backflow reduces output flow.
Solution: Replace new wear-resistant alloy sealing ring.
(3)Air Residue Inside Pump Body & Pipeline
Cause: Unfinished exhaust before startup generates air lock.
Solution: Open exhaust port to fully drain internal air before starting pump.
(4)Motor Reverse Rotation
Cause: Three-phase power wiring wrong phase sequence.
Solution: Swap any two motor power lines to correct rotation direction.
(5)Inlet Valve Blocked or Not Fully Opened
Cause: Filter screen blocked by sludge, inlet valve half closed.
Solution: Clean filter screen, fully open inlet cut-off valve.
(6)Actual Head Exceeds Pump Rated Design Head
Cause: Pipeline resistance too large, delivery height beyond pump parameter range.
Solution: Optimize pipeline layout to reduce resistance or select higher-head YW pump model.

Need More Information?

If you need more technical information about YW Type Liquid-Submerged Sewage Pump or have any questions regarding installation, operation, maintenance and model selection, please feel free to contact the engineering and technical team of Haquan Pump & Valve. We will provide you with professional and thoughtful service wholeheartedly. Your full satisfaction is our top priority.

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