Well Pump Keeps Running: Causes & Fixes

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Cause 1: Faulty or Misadjusted Pressure Switch

The pressure switch tells the pump when to turn on and off based on system pressure. If its contacts are burned or its cut-off setting has drifted, the pump will never receive the signal to stop.

1. Turn off the circuit breaker to the pump before touching anything electrical.
2. Locate the pressure switch — it’s a small box (usually gray) mounted on the pipe near the pressure tank.
3. Remove the cover and inspect the contacts for pitting, burning, or corrosion. Burned contacts mean the switch needs replacement.
4. Check the cut-in and cut-out pressure settings (commonly 30/50 psi or 40/60 psi). Adjust the range nut only if you are confident in the correct settings for your system.
5. If contacts are damaged or adjustment doesn’t help, replace the switch.

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Cause 2: Waterlogged or Failed Pressure Tank

A pressure tank uses an air charge or bladder to maintain steady pressure. When the bladder fails or the air charge is lost, the tank fills completely with water and cannot maintain pressure, forcing the pump to run continuously.

1. Tap the side of the pressure tank from bottom to top — a healthy tank sounds hollow in the upper half; a waterlogged tank sounds solid all the way up.
2. Turn off the pump breaker and open a nearby faucet to release pressure.
3. With a tire pressure gauge, check the Schrader valve air stem (usually on top of the tank). It should read 2 psi below your pump’s cut-in pressure (e.g., 28 psi for a 30/50 system).
4. If the air reads zero and water sprays from the valve, the bladder is ruptured — the tank must be replaced.
5. If the air is simply low, use a bicycle pump or air compressor to inflate to the correct psi while the tank is depressurized and empty.
6. Restore power, check for normal pressure cycling (pump on at cut-in, off at cut-out).

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Cause 3: Failed or Stuck Check Valve

A check valve prevents water from flowing back down into the well when the pump stops. If it fails in the open position, pressure bleeds back and the pressure switch triggers the pump to run again immediately.

1. Note whether your pressure gauge drops slowly to zero shortly after the pump shuts off — this points directly to a leaking check valve.
2. Turn off the pump breaker and relieve system pressure at a faucet.
3. Locate the check valve — it is typically found just above the submersible pump inside the well casing, or on the discharge pipe in the pump house for a jet pump.
4. For an in-line check valve on a jet pump, close the shutoff valves on either side, remove the valve, and inspect the flapper or spring mechanism for debris or wear.
5. Replace the check valve if the flapper doesn’t seat properly or shows cracking.
6. For a submersible check valve inside the well casing, this is a job for a licensed well contractor.

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Cause 4: Pressure Gauge Failure

A clogged or broken pressure gauge can give a false zero reading, making it appear the system isn’t building pressure even when it is — or it can prevent the pressure switch from sensing true system pressure.

1. Compare the gauge reading to a known-good portable gauge tapped into the system if possible.
2. Turn off the breaker and depressurize the line at a faucet.
3. Unscrew the gauge — they typically thread directly into a tee fitting.
4. Inspect the port for mineral scale or debris blockage. Use a small pick to clear any sediment from the port.
5. Install a new gauge with thread-seal tape on the threads, restore power, and verify normal pressure readings.

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Cause 5: Low Well Water Level or Depleted Well

During drought conditions or periods of heavy use, the water table can drop below the pump intake. The pump draws air instead of water, cannot build pressure, and runs without stopping in a futile attempt to meet demand.

1. Turn off the pump immediately to prevent pump damage from running dry — submersible pumps rely on water for motor cooling.
2. Wait 1–2 hours to allow the well to recover, then restore power briefly and watch the pressure gauge.
3. If pressure builds normally after recovery, the well yield is simply too low for your usage rate — reduce simultaneous demand and consider a storage tank solution.
4. If the well fails to recover, contact a licensed well driller to assess well depth, static water level, and pump placement.
5. Do not continue running the pump dry — motor burnout can occur within minutes.

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Cause 6: Worn or Failing Pump Motor

An aging submersible or jet pump motor may run continuously as it loses the ability to generate adequate pressure — even when the rest of the system is functioning correctly.

1. Record how long the pump has been in service. Submersible pumps typically last 10–15 years; jet pumps 10–20 years.
2. Listen for unusual sounds: grinding, humming without starting, or a hot-burning smell near the pump housing all indicate motor problems.
3. Check the pump capacitor (on single-phase motors) — a swollen or leaking capacitor prevents the motor from reaching full speed and building pressure.
4. If the capacitor tests faulty with a multimeter capacitance setting, replace it before condemning the entire pump.
5. If the motor itself has failed, have a licensed well contractor pull and replace the submersible pump, or replace the jet pump assembly.

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Frequently asked questions

For further guidance on well water systems and maintaining safe drinking water, visit the CDC Private Wells resource page.

Related problems

• Well Pressure Switch Not Turning On: Fix It Fast
• Well Pump Not Building Pressure: Fix It Fast
• Well Pump Not Working – Troubleshooting & Repair Guide
• Well Pump Losing Prime: Causes & Fixes

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