A bore pump that stops delivering water can bring a home, livestock operation, irrigation system or business to a standstill. Knowing how to troubleshoot bore pump faults helps narrow down whether the issue is power supply, controls, pipework, water level or the pump itself - without making an unsafe repair attempt.
Start with what has changed. A sudden loss of water after a storm points to electrical supply or surge damage. Falling pressure over weeks may indicate worn pump components, a blocked filter or a dropping bore water level. A pump that runs constantly but cannot build pressure needs a different check again.
Start with safety and the obvious checks
Bore pumps are commonly submersible units installed deep below ground, often connected to automatic controllers, pressure tanks and mains electricity. Do not remove a bore pump, open electrical connections or bypass a protection device while power is connected. Water and electrical faults are a serious combination.
Before inspecting anything, isolate power at the switchboard and confirm the pump circuit is off. If the safety switch or circuit breaker has tripped, reset it once only after checking for obvious water ingress or damage. If it trips again, leave it off and arrange a licensed electrician or pump technician. Repeated resetting can damage the motor and may indicate a cable or motor insulation fault.
Check that the water supply issue is genuinely limited to the bore system. If a rainwater tank, town supply changeover or another pump feeds the property, make sure the correct source has been selected. Then inspect accessible valves, filters and pipework. A partially closed isolation valve, blocked cartridge filter or damaged poly pipe can produce symptoms that look like pump failure.
How to troubleshoot bore pump faults by symptom
The symptom is usually the quickest way to reduce the possible causes. Listen to the system, note any controller lights or fault codes, and observe whether pressure rises, falls or remains steady.
The pump will not start
If there is no sound from the pump when water is demanded, begin at the controls. Check the isolator, circuit breaker, pressure controller or pressure switch, and any dry-run protection device. A pressure tank system may not call for the pump if the pressure switch is set incorrectly or its sensing line is blocked.
A controller showing a power light but no pump operation can indicate a control fault, failed capacitor, damaged wiring or an open motor circuit. Single-phase bore pumps often rely on a control box with a capacitor and overload protection. These components can fail, but testing them involves live electrical equipment and should be handled by a qualified technician.
Also consider low bore water level. Some systems lock out after dry running and require a manual reset or a timed restart. Do not repeatedly force a restart if the bore may be low. A submersible pump depends on surrounding water for cooling, and running dry can quickly cause motor damage.
The pump runs but no water comes out
A running pump with no delivery can mean the water level has dropped below the pump inlet, especially after a long dry period or heavy irrigation demand. It may also point to a split rising main, failed non-return valve, blocked pump intake or a blockage in the delivery line.
Check any pressure gauge on the discharge line. If the gauge shows little or no pressure while the pump runs, the problem may be at the pump, in the bore, or in a major leak before the gauge. If pressure rises normally at the pump system but no water reaches taps or irrigation zones, look downstream for closed valves, blocked filters, clogged solenoids or damaged pipework.
A sudden no-flow condition after the pump has been operating normally can also be caused by a broken pipe connection down the bore. This cannot be confirmed from the surface alone. The pump and rising main may need to be lifted and inspected by a bore pump specialist.
Water pressure is weak or fluctuates
Weak pressure is not always a pump problem. Start by cleaning or replacing filters and checking that valves are fully open. Sediment, iron build-up and scale can restrict strainers, filters and irrigation fittings, particularly where bore water has high mineral content.
If filters are clear, compare the pressure gauge reading when no water is being used with the reading while a tap or irrigation zone is open. A large pressure drop can indicate a worn pump, undersized pipework, a leaking line or a pressure tank issue. In systems with a pressure tank, a ruptured bladder or incorrect air charge causes frequent pump cycling and uneven pressure.
For irrigation, confirm the pump duty matches the job. A bore pump may supply a small domestic demand well but struggle when several sprinklers, long pipe runs or elevated storage tanks are added. Flow rate and head must be assessed together. Adding a larger pump without checking bore yield, cable size and pipe pressure rating can create a more expensive fault.
The pump starts and stops too often
Short cycling is hard on motors, relays and pressure switches. On a pressure tank system, first check whether the pressure tank has lost its air charge or has a failed bladder. With power isolated and water pressure released, the tank air pressure should generally be set to suit the pressure switch cut-in setting. The correct setting varies by system, so follow the tank and controller specifications rather than guessing.
A leaking non-return valve can also cause pressure to bleed back into the bore. The controller then sees a pressure drop and starts the pump even when no water is being used. A concealed leak in the property pipework may produce the same result. If the pressure drops when all outlets are closed, isolate sections of the system where possible to identify whether the loss is on the bore side or the property side.
The water is dirty, sandy or discoloured
Some sediment is normal after a new bore is developed or after a long period without use. Persistent sand, however, can wear pump impellers, block filters and damage valves. It may indicate that the pump is installed too low, the bore screen has deteriorated, or the pump flow rate is drawing water too aggressively through the formation.
Do not simply fit a finer filter and continue operating. Fine filtration may protect household fixtures, but it will not prevent abrasive material from reaching the pump if the sand originates in the bore. A technician can assess pump depth, bore condition, flow rate and whether a different pump configuration is required.
Check the bore water level and demand pattern
A bore can produce clear water for years and then become unreliable because groundwater conditions change. Seasonal rainfall, nearby extraction, extended dry conditions and increased property demand can all lower the available water level.
Signs of low yield include water that starts strongly then fades, dry-run alarms after extended use, or a pump that recovers after being left off for several hours. Reduce demand while the issue is investigated. Stagger irrigation zones, avoid filling tanks and running sprinklers at the same time, and use a storage tank where practical to separate bore recovery from peak demand.
A proper bore assessment may include static water level, pumping water level, recovery rate and actual pump output. These measurements determine whether the existing pump is suitable or whether the system needs dry-run protection, altered pump depth, reduced flow or a tank-based arrangement.
Know when the pump needs to come out
Some faults can be resolved at the surface. Filters, pressure settings, controllers, pressure tanks and accessible leaks are often serviceable without lifting the pump. But a failed submersible motor, damaged cable, worn impellers, blocked intake, split rising main or faulty down-hole non-return valve normally requires the bore pump to be removed.
Do not attempt this with a rope and a few helpers. Bore pumps can be heavy, the rising main may be full of water, and a damaged cable or pipe can be lost down the bore. Safe removal requires suitable lifting equipment, correct joining methods and care not to damage the bore casing.
When recording the fault for a technician, include the pump make and model if known, bore depth, controller type, pressure readings, fault codes, when the problem began and whether the pump runs. This information helps determine whether the likely issue is electrical, hydraulic or bore-related before work begins.
A reliable bore system is built around the whole installation, not only the pump. If faults are recurring, Foundation Pumps can help assess the pump, controls, protection, pipework and water demand together, so the replacement or repair suits the actual application. Acting early on pressure changes, unusual cycling or dirty water is usually far cheaper than waiting for a complete loss of supply.