Home Well Pump Running But No Water? 8 Causes and How to Test Each One
Short answer: Before assuming the pump is dead, confirm whether it is actually running. If it hums or pulls current but no water arrives, the fault is almost always one of eight things — a dry well, a failed pressure switch or waterlogged tank, a leaking check valve, a blocked impeller, a tripped control box, a broken drop cable, a closed valve, or an air lock. If the pump is silent, the problem is upstream: power, control box or motor winding. The table further down separates those two cases, and each cause below has a test you can run with a pressure gauge, a bucket and a multimeter.
Never pull a submersible pump out of a well by hand, and never work on a drop pipe that is under pressure.
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| What you observe | What it usually means | Go to |
|---|---|---|
| Pump hums, breaker holds, no water | Motor is energised but not moving water | Causes 1–4, 7, 8 |
| Pump silent, no hum, breaker holds | No power reaching the motor | Causes 5–6 |
| Breaker or overload trips immediately | Short circuit, seized motor or bad capacitor | Cause 5 |
| Pump runs continuously, never shuts off | Water level below intake, or a leak on the discharge side | Causes 1, 3 |
This is the single most common cause, and it is the first thing experienced well owners check. The pump sits below the water level; when a dry season, a neighbour’s new well, or increased household demand pulls that level below the pump intake, the pump keeps spinning with nothing to move.
Symptoms: the pump runs and runs, output is weak then drops to nothing, and the water may turn muddy or gritty right before it stops — the pump is pulling the last of the water and the sediment with it.
How to test it: compare against the well completion report if you have one, or have the static level measured with a water-level meter. Some drillers will do this for a small fee. Washington State’s Department of Health publishes a plain-language guide to falling well levels, which is worth reading before you assume the pump has failed.
What to do: if the well still has water but the pump sits too high, the pump can be lowered (subject to the well’s recovery rate). If the level is genuinely falling, the correct fix is a low-water cut-off plus dry-run protection, and longer term a deeper well. Running a submersible pump dry is the fastest way to destroy it — the water is the motor’s coolant.
A submersible pump does not decide when to run. The pressure switch does. When the tank cannot hold its air charge, the switch clicks on and off rapidly and the pump short-cycles — and short cycling is what actually kills motors.
Symptoms: you hear repeated clicking near the tank whenever a tap is open, the pressure gauge needle swings fast between the cut-in and cut-off values, water pressure is strong for a few seconds and then falls to a trickle, and taps spit air.
How to test it:
The check valve stops water from draining back down the drop pipe every time the pump stops. When it leaks, the system loses pressure between cycles, the pump restarts far too often, and in the worst case the water column drains back far enough that the pump has to lift it again from scratch.
How to test it: with the system at pressure, close the valve downstream of the pressure tank and note the gauge reading. Wait ten minutes. If the pressure has dropped, the check valve is leaking or stuck open.
Sand, grit, iron scale and mineral build-up all attack impellers. A partially blocked impeller cannot make its rated head, so the pump runs, sounds normal, and moves far less water than it should.
How to test it: measure the current the pump draws. Use the 10-amp setting on a multimeter in series with one leg of the circuit. Expect a brief start-up spike (commonly in the 15–20 A range on larger models) that settles to a lower running figure. If the pump holds a high amperage instead of settling, it is working too hard — usually a clog, a damaged impeller, or mechanical resistance.
This is also the point at which pump selection matters: a pump specified with a generous head margin, a stainless-steel stage stack and a sand-tolerant design survives dirty water far better than a budget unit running at its limit.
Three-wire submersible pumps use a control box containing a start capacitor and a relay. A failed capacitor gives you the classic symptom: the pump hums, cannot start, and the overload trips.
Symptoms: a burnt smell near the control box, a bulged or leaking capacitor, or the pump humming without starting.
How to test it: with power off, discharge the capacitor safely and have it tested — most electrical shops will do this in minutes. A replacement capacitor is inexpensive; a motor that has been sitting stalled on a bad capacitor is not.
Years of vibration and water movement chafe cable, and a splice that was never properly heat-shrunk fails. When a conductor breaks, the pump simply stops — no hum, no current.
How to test it: with power off and the pump wires disconnected from the control box, measure resistance between the leads with a multimeter and compare against the resistance range printed on the pump or motor label. A reading of “OL” (open loop) means a broken wire or open winding. A reading well below the specified range points to a short inside the motor. Both cases mean pulling the pump.
Check the cheap things first — installers regularly get called out to a well that was simply valved off after servicing, or a line that froze at the first cold snap.
Walk the discharge line: every gate valve, every isolation valve, the fitting where the line enters the house. On a cold-climate system, check the run between the well head and the building, which is the section most likely to freeze.
Most common on jet pumps, but a submersible system can air-lock after work on the drop pipe or after the well has been drawn right down. The pump is moving air instead of water, so the gauge stays low and the taps sputter.
What to do: open the highest tap in the house and let the system run to purge the air. Persistent air at the taps usually points back to cause 1 (the intake is drawing air) or cause 3 (the check valve is letting the column drain back).
| Symptom | Most likely cause | First test |
|---|---|---|
| Runs continuously, no water | Well level below intake (1) | Static water level |
| Clicks rapidly, pressure surges | Waterlogged tank (2) | Air valve + gauge |
| Loses pressure when idle | Check valve (3) | 10-minute pressure hold |
| Runs, low flow, high amperage | Blocked impeller (4) | Current draw |
| Hums, will not start | Capacitor / control box (5) | Capacitor test |
| Completely silent | Cable or winding (6) | Resistance test |
| No water after servicing | Closed valve (7) | Walk the line |
| Taps spit and sputter | Air lock (8) | Purge at highest tap |
How do I know if my well has run dry? The pump runs continuously without building pressure, output falls away and the water turns gritty or muddy just before it stops. A static water level measurement confirms it. Never keep running a pump that is dry — it overheats within minutes because water is the motor’s only coolant.
Can a waterlogged pressure tank stop water completely? Not usually by itself, but it can drive the pump into rapid short cycling until the overload trips, which looks like total failure. If water comes out of the tank’s air valve, the bladder has failed and the tank should be replaced.
What should my pressure tank pre-charge be? About 2 PSI below the pressure switch cut-in setting. On a 30/50 switch that is roughly 28 PSI, measured with the tank fully drained and the power off.
Why does my pump run for a few seconds and then stop? That is short cycling, and it is nearly always the tank (lost air charge, ruptured bladder or undersized drawdown) or a leaking check valve. Every cycle stresses the motor, so fix it promptly.
Is a multimeter test safe for a homeowner? Measuring resistance or current means opening an electrical enclosure on a 220–240 V circuit. If you are not confident working with mains wiring, stop at the visual and pressure checks and hand the electrical diagnosis to a qualified technician.
How long should a submersible pump last? Life depends far more on water quality and how the pump is run than on the pump itself. Sand-laden water, dry running and short cycling are the three great killers. A correctly sized pump with dry-run protection and a tank that matches its drawdown will comfortably outlast a mismatched one.
Look back over the eight causes and you will notice that three of them — dry running, short cycling and abrasion — account for the vast majority of premature submersible pump deaths. None of those three is really a pump-quality problem. They are system-design problems: an intake set too high, a tank too small for the pump, a well producing sand.
That is why we build our deep well and borehole pumps with stainless-steel stage assemblies and offer matching pressure stabilisation tanks sized to the pump’s drawdown rather than to a price point. If you are specifying a system and want a second opinion on the drawdown maths, the technical team at our factory will run the numbers with you before you order.
Sources and further reading