Borehole Pump Troubleshooting Guide
Borehole Pump Troubleshooting Guide
A Borehole pump is often thought to be working fine as it operates out of sight, submerged deep underwater, or within a well. It is not until the pump stops delivering water that fault finding begins. The first check when any pump stops working is to understand if anything has changed recently possibly contributing to the pump stoppage.
If nothing has changed recently then it would be prudent to work through our troubleshooting guide below to try and determine the reason for failure.
Problem | Possible Cause | Remedy |
Motor Does not Start | Power / Voltage incorrect | Check voltage at each terminal is within +- 10%. Check phase continuity. If pump is solar powered, check age of panels as their efficiency decreases 1% per year, and more panels may need adding to maintain required power supply |
Pump Tripping | Check fuse, check water level in borehole to establish if pump is running dry. If in open body ensure cooling sleeve is being used. Check phase continuity and cable for water ingress | |
Pressure Switch Defective | Check voltage on switch and contact points | |
Control Box Malfunction | Check condition, voltage and resistance within unit. Repair or replace | |
Wiring | Have motor resistance checked, and voltage. Check for water ingress | |
Pump Seizure | Check for sand ingress in base of pump or damage. Check amps drawn, if more than 3-6 times starting current pump will need dismantling, cleaning, repair and rebuilding. | |
Frequent Pump / Motor Starts | Pressure Switch Defective | Check voltage on switch and contact points |
Check Valve Failure | A check valve which is worn or is kept open by particles will not withhold pressure within the pump. | |
Leakage | Check pipework for signs of leaks | |
Pressure Switch Defective | Check voltage on switch and contact points | |
Motor Always Operational | Pressure Switch Defective | Check voltage on switch and contact points |
Low Water Level | Low water level is causing pump to recirculate water. Install pump protection device. Check water level and determine if low level alarm should be fitted. | |
Leakage | Check pipework for signs of leaks | |
Worn Pump | As symptoms are similar to that of a pipe leak it is prudent to reduce the pressure switch setting. If pump stops dismantle pump and check condition of parts | |
Coupling Loose or motor shaft broken | Check Coupling and Damaged Shaft. Replace worn or damaged parts | |
Suction Strainer Blocked | Rinse, repair / replace as required | |
Check Valve Closed | If not operational replace | |
Control Box Malfunction | Check condition, voltage and resistance within unit. Repair or replace | |
Motor Operational however overload protection trips | Power / Voltage incorrect | Check voltage at each terminal is within +- 10%. Check phase continuity. |
Overload Protection Overheating | Overload Protection switch must be located in shaded area, have adequate ventilation and not be hot to touch | |
Control Box Malfunction | Check condition, voltage and resistance within unit. Repair or replace | |
Pump Tripping | Check fuse, check water level in borehole to establish if pump is running dry. If in open body ensure cooling sleeve is being used. Check phase continuity and cable for water ingress | |
Pump Worn | Check operational current. Replace parts, pump or motor | |
Little or no Liquid Delivery | Check Valve Closed | If not operational replace |
Pump Airlocked | Continually start pump until required flow is delivered | |
Back Pressure | Differential pressure is too great for the pump. Check level of water in borehole as may be different to what was originally specified. Replace pump, increase motor size, or increase volume of water in borehole | |
Particle Ingress | Check suction strainer and pump inlet for blockage, or high sand ingress | |
Insufficient Water | Check depth of borehole and amount of water within well | |
Gas and Air present | Restart pump to clear. If water is not delivered speak with well driller | |
Excessive Pump wear | Ensure pump is operating on curve. Check for solid ingress, ensure check valve is operating as required and that pump is not working against closed discharge. | |
Incorrect Rotation | Check direction of rotation. Change phases as required | |
Pump Activates without Demand | Check Valve Faulty | If not operational replace. Close valve between tank and house and check pressure with all taps closed and boiler off. See if pressure drop occurs |
Slow Leak | Check house for leak. Close valve between tank and house and check pressure with all taps closed and boiler off. See if pressure drop occurs |
