The following diagnostic guide applies when your centrifugal pump motor is running but water problems exist.
For any bore pump problems call us on 9246 0111 seven days a week for telephone advice or to book a service Perth metro-wide. You can also visit our main website here.
(If pump is not starting at all then an electrical problem exists not covered in this guide. Call to book a visit from one of our water bore / pump specialist electricians who have all the necessary tools for diagnosis or repair of pump electrical problems. More info covered here .)
Pump runs but no water?
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Priming – suction pipe not completely filled with water.
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The check valve has failed
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Discharge head too much – depth to water beyond pump range.
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Suction lift too high. Suction pipe may be too small or long, causing excessive friction loss.
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The Impeller is blocked.
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Suction pipe/screen/strainer completely blocked.
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Pump motor running in reverse (check direction).
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Air pocket in suction line.
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Air leaks in suction line and/or shaft seal, gland packing.
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Discharge line closed off, solenoid valve not opening or gate valve closed.
Poor flow?
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Priming – casing and suction pipe not completely filled with liquid.
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Discharge head higher than anticipated. Check friction loss in piping.
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Suction lift too high. Suction pipe may be too small or long and causing excessive friction loss.
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Impeller partially plugged.
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Suction pipe/screen /strainer partially blocked.
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Pump motor running in reverse (check direction).
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Air pocket in suction line.
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Air leaks in suction line and/or shaft seal, gland packing.
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Foot valve too small.
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Suction pipe not into the water enough after draw-down.
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Mechanical faults such as the Impeller damaged, gland-packing of shaft seal damaged or wear rings worn.
Water pumps OK then stops?
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Leak in suction line.
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Leakage of air into pump casing.
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Air pocket in suction line.
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Suction lift too high.
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Insufficient groundwater.
Not Enough Pressure?
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Speed to low.
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Air in water.
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Wrong impeller diameter.
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Mechanical fault – Wear rings worn. Impeller damaged. Shaft seal or gland-packing damaged.
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Wrong direction of rotation.
Water pumps OK then stops but pump still running
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Leak in suction line.
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Leakage of air into pump casing.
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Air pocket in suction line.
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Suction lift too high.
Pump is noisy.
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Hydraulic noise – cavitation, too much suction head.
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Mechanical Faults including – pump and drive unit out of alignment ,rotating elements binding, shaft bent, bearings worn.
Pump leaks .
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Gland Packing worn/loose. Shaft seal damaged.
- Packing incorrectly inserted or not properly run in.
- Shaft scored.
- Housing damaged.