Signs Your Well Pump Is Going Bad
The clearest signs your well pump is going bad are pressure that sags or drops off fast, sputtering taps, a pump that cycles on and off with nothing running, new noises, and a power bill that creeps up for no reason. Here's how to tell if the well pump is bad rather than the tank or the switch: rule out those cheaper parts first, because they cause many of the same symptoms.
That order matters. A pressure tank or pressure switch costs a fraction of a pump, and a contractor who pulls a pump that didn't need pulling still bills for the day.
The warning signs
HomeGuide's list of failing-pump symptoms is a good starting point:
- Low or fluctuating pressure, or pressure that drops off quickly while you're using water.
- No water at all.
- Grinding, clicking or rattling from the pump area.
- The pump turning on and off repeatedly when no one is using water.
- Electric bills that are higher than usual.
- Sputtering faucets or air in the water.
- Dirty or cloudy water.
None of these proves the pump is the problem. Here's how to sort them out.
Sign 1: pressure drops or fades
If the shower starts strong and then goes weak, and the pump runs longer and longer to catch up, the pump may be worn. Franklin Electric notes that a worn pump shows symptoms much like a drop pipe leak or a low water level in the well. All three mean the pump can't push as much water as it used to.
Before you blame the pump, look at the pressure gauge near the tank. If it never climbs to the cut-out pressure printed on the switch, something's limiting flow. Pentair's troubleshooting chart for little or no water lists a low water level, low voltage, a plugged intake screen, a stuck check valve, and worn impellers. Only the last one is a worn-out pump. Our low water pressure from a well page goes through the rest.
Sign 2: the pump runs constantly or never shuts off
A pump that runs nonstop with the taps closed is either fighting a leak, starving for water, or too worn to build pressure. Franklin's chart for a motor that runs continuously lists a stuck or welded pressure switch, low water in the well, a leak, a worn pump, a broken shaft or loose coupling, a blocked intake screen, and a check valve stuck closed. See well pump keeps running for the checks in order.
Sign 3: rapid on-off cycling
Rapid cycling often gets blamed on the pump. Pentair's list for a pump that starts too often is a waterlogged tank, a bad or misadjusted switch, leaks, a leaking drop pipe, and a switch mounted too far from the tank. It says to set the tank's precharge 2 psi below the cut-in pressure. Check that before anything else. Our well pump short cycling page covers it.
Left alone, though, short cycling does hurt the pump. Franklin says to run a motor at least one minute per start to clear the heat from starting current.
Sign 4: sputtering faucets, air or dirty water
Air spitting from the taps can be a pump drawing air because the water level has dropped near the intake. It can also be gas in the well water, which Pentair lists as a cause of air or milky water. Sand or grit in the water is a separate warning: Franklin lists sand as one reason a pump binds up. See air in water lines and sediment and sand in well water.
Sign 5: higher electric bills
A pump that runs longer to deliver the same water uses more power. A worn pump is one cause. So is a leak you can't see, or a waterlogged tank making the pump start more often. If the bill jumped and the pump seems to run all the time, an electrician or well contractor can compare the running amps against the motor's rating. Franklin's fix for a worn pump or motor starts with exactly that comparison.
Sign 6: tripped breakers or no start
A pump that trips its breaker, or hums without starting, may have a failing motor, a bad start capacitor, or a damaged cable. Pentair lists a blown starting capacitor as one cause of a breaker or overload tripping on start. Franklin lists a bound pump, a damaged cable or motor, and a control box fault. Our page on a well pump that keeps tripping the breaker covers what to check.
Rule these out first
| Symptom | Check before blaming the pump |
|---|---|
| Rapid cycling | Tank air charge and bladder, then the switch |
| Pump won't start | Breaker, pressure switch contacts, control box |
| Low pressure | Filters, switch setting, tank precharge |
| Runs nonstop | Leaks, toilets, outdoor spigots |
How to tell if the pressure tank is bad
Press the air valve on top of the tank. Water coming out means a torn bladder. A tank that's full of water sounds solid when you knock on it near the top. Pentair says to check the tank's precharge every year. More on that in waterlogged well pressure tank.
How to tell if the pressure switch is bad
A switch with burned or pitted contacts may not close at all, or may chatter. Franklin notes that improper contact of the switch points can drop the voltage below line voltage, and says to clean the points or replace the switch. A switch with welded contacts keeps the pump running nonstop. See well pressure switch problems.
Confirming the pump is bad, and what it costs
Once the tank, switch and leaks check out, a well contractor confirms the pump with electrical tests at the surface: running amps against the nameplate and an insulation test with a megohmmeter. Franklin says a reading below 0.50 megohms on a motor in the well means insulation damage that needs to be found and repaired. Those numbers tell the contractor whether to pull the pump before anyone lifts it.
HomeGuide's 2026 costs, parts and labor included:
| Repair | Typical cost |
|---|---|
| General well pump repair | $300 to $600 |
| Pressure switch | $150 to $200 |
| Start capacitor | $150 to $300 |
| Control box | $300 to $600 |
| Pressure tank replacement | $800 to $1,500 or more |
| Pump replacement | $1,000 to $2,500 or more |
HomeAdvisor's minimum house call runs $100 to $150. If the pump is old and the repair quote is high, compare it with our well pump replacement cost page and read how long well pumps last.
FAQ
How can you tell if your well pump is bad?
Look for pressure that fades, a pump that runs nonstop, sputtering taps, new noises and a higher power bill. Then rule out the pressure tank, the pressure switch and leaks, since they cause the same symptoms. If those check out, a contractor confirms the pump with amp and insulation tests.
How do you tell if a submersible well pump is bad?
You can't see a submersible pump, so the clues come from the surface: the gauge, the switch and the electrical readings. A worn submersible behaves much like a drop pipe leak or a low water level. A contractor's amp draw and megohm readings settle it before the pump is pulled.
How do you tell if a well pump capacitor is bad?
A bad start capacitor usually shows up as a motor that hums but won't start, or one that trips the breaker on start. Pentair lists a blown starting capacitor as a cause of tripping on start and says to check the control box. The capacitor sits in the control box, and testing it means working inside a box that holds a charge, so leave it to a pro.
How do you tell if a jet pump is bad?
Jet pumps sit above ground, so you can listen and look. A jet pump that runs but won't build pressure, loses prime often, or screeches from worn bearings is in trouble. Check the foot valve and suction line for air leaks first; see jet pump problems.
Where is my well pump located?
A submersible pump sits down inside the well casing, often far below ground. A jet pump sits above ground, usually in a basement, crawl space or well house, near the pressure tank. If you only see a tank and a switch indoors and no motor, you have a submersible.
Sources
- HomeGuideWell Pump Repair Cost (opens in a new tab)
- Pentair (Simer)2- and 3-Wire Submersible Pumps: Installation and Operation Manual (SIM280) (opens in a new tab)
- Franklin ElectricAIM Manual: Submersible Systems, 60 Hz (opens in a new tab)
- HomeAdvisorHow Much Does Well Pump Repair Cost? (opens in a new tab)