Reasons and Solutions for Submersible Sewage Pump Failing to Lift Water

No Water Output at All

1. Power Supply & Starting Fault: Power phase loss; low voltage; broken cable or winding; blown fuse or poor switch contact in control cabinet.

Check power connections, switches, and fuses. Use a multimeter to measure voltage and resistance. Repair broken circuits.

2. Pump Not Primed / Air Pocket: Pump body or suction pipe not fully filled with water, containing air.

Stop the pump. Completely fill the pump body and suction pipe with water before restarting.

3. Impeller Jammed or Pump Shaft Issue: Impeller jammed by entangled debris; bent pump shaft or seized bearing.

Hoist the pump out. Clean debris from the impeller. Disassemble for inspection; straighten or replace the pump shaft/bearing.

4. Pump Running in Reverse: Incorrect power phase sequence causes impeller to rotate backward.

Swap any two of the three power supply wires.

Insufficient Flow Rate

1. Inlet Blockage or Leakage: Impeller, pump body, or foot valve blocked by debris; air leak in suction pipeline, flange, or seal.

Remove blockage. Inspect pipelines; apply sealant to leaks or tighten bolts.

2. Worn Impeller or Seal: Impeller cavitation or wear; severely worn wear ring (seal ring) causing increased internal leakage.

Replace the worn impeller or wear ring.

3. Improper Installation/Operating Conditions: Actual head exceeds pump's rated head; insufficient submersion depth of inlet.

Replace with a pump of higher head, or reduce the actual system head. Ensure the pump is installed below the dynamic water level.

4. Medium Issue: Density or viscosity of the pumped liquid is too high.

Dilute the medium with water or replace with a more suitable pump model.