Well pump not working? A symptom-by-symptom repair guide

By Alejandro · Updated October 15, 2026 · How we pick

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Safety first

• Well pumps run on 240 volts. Switch off the pump breaker before opening a pressure switch or control box, and confirm it's dead with a meter. Pressure switch terminals stay live whenever the breaker is on.
• Relieve pressure before removing a gauge, switch or tank fitting: power off, then open a faucet until the gauge reads zero.
• Don't keep resetting a breaker or overload that trips again right away. That's a short or a stalled motor, not bad luck.
• Don't run a pump dry. If the pump runs and no water comes, shut it off. Running dry can ruin a pump that was otherwise fine.

Tools and parts that help

You won't need all of these. A gauge and a meter diagnose most problems; the parts are the common replacements.

1. Start here: a pressure gauge you can trust

   Winters PFQ804 2.5" Liquid-Filled Pressure Gauge, 0–100 psi

   Most well problems show up on a pressure gauge before anything else: where the pump kicks on, where it shuts off, and how fast pressure falls. The glycerin fill steadies the needle when the pump starts. Skip it if your existing gauge reads 0 with the system drained and moves smoothly; old gauges often stick, so replace yours if in doubt.

   • 0–100 psi, 2.5" dial
   • 1/4" NPT bottom mount
   • Glycerin filled; 304 stainless case
   • ±1.5% of full scale
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2. Best meter for voltage, amps and capacitors

   Klein Tools CL810 Auto-Ranging Clamp Meter

   Lets you confirm power at the pressure switch, read the pump's amp draw, and test a start capacitor. Those three readings narrow down most electrical faults. Skip it if you aren't comfortable working near live 240V circuits; pay a pump pro for the diagnosis instead.

   • AC/DC current to 600A, True RMS
   • 1000V AC/DC
   • Capacitance to 6,000 µF
   • Low-impedance mode; non-contact voltage detector
   • CAT IV 600V / CAT III 1000V
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3. Most common replacement part

   Square D Pumptrol 9013FSG2J24 Pressure Switch (40/60 psi)

   The standard switch on most well systems. Burned contacts or a clogged inlet tube are among the most common reasons a pump won't start or won't stop. Skip it if your pump uses a constant-pressure controller (like a Grundfos SQE): those use a pressure sensor, not this switch.

   • Factory set 40 psi on, 60 psi off
   • 1/4" female NPT
   • Rated 1.5 HP at 115V
   • Nitrile diaphragm; 220 psig max
   • 30/50 version: 9013FSG2J21
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4. For 3-wire pumps that hum or trip

   Franklin Electric QD Control Box for 3-Wire Motors

   On a 3-wire pump, the start capacitor and relay sit in this box, not in the well. A failed capacitor or relay is a far cheaper fix than a new pump. Skip it if you have a 2-wire pump (no box) or a constant-pressure drive; and a box must match your motor's brand, horsepower and voltage exactly.

   • For Franklin 3-wire, single-phase motors, 1/3–1 HP
   • Start capacitor + solid-state QD relay
   • Match HP and voltage: 2801054915 = 1/2 HP 230V; 2801084915 = 1 HP 230V
   • Disconnects internal parts when the lid opens
   • UL listed; outdoor rated
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5. 

   If your tank is waterlogged and can't be recharged

   Amtrol Well-X-Trol WX-203 (32 gal)

   The tank most well installers reach for: a steel shell, a fixed butyl diaphragm and a long warranty. Skip it if your tank sits in a damp crawlspace or near the coast; steel can rust from the outside, and a composite tank may last longer there.

   • 32 gal total; 8.6 gal drawdown at 40/60
   • Factory precharge 38 psi; 150 psi max
   • Heavy-duty butyl diaphragm
   • 1" connection; 45" tall x 15-3/8" wide
   • 43 lb; 7-year limited warranty
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Find your symptom

Step-by-step: no water

1. Check the breaker. Look for a tripped double-pole breaker labeled "well" or "pump". Reset it once. If it trips again, stop and skip to the breaker section below.
2. Read the gauge. If pressure is at or below the cut-in setting (often 40 psi on a 40/60 switch) and the pump isn't running, the problem is between the breaker and the motor.
3. Check the pressure switch. With power off, pull the cover and look at the contacts. Pitted, burned or welded contacts mean replace the switch. Also check the small tube or nipple under the switch; iron and sediment clog it so the switch can't sense pressure. Wells with iron or sediment do this often.
4. Confirm voltage. With the meter, check for 240V at the switch's load side when the contacts close. Voltage needs to be within about 10% of the motor's rating.
5. Check the control box (3-wire only). A failed start capacitor or relay leaves the motor humming without starting, then tripping the overload. Many Franklin QD boxes cost far less than a pump. Match horsepower and voltage exactly.
6. Still nothing? The remaining causes are the drop cable, a splice, the motor or the pump. Those need insulation and winding resistance tests and usually pulling the pump. That's a pump-pro job.

Step-by-step: pump short-cycles

Rapid on-off cycling is the most common well complaint, and it kills pumps and switches if you ignore it.

1. Tap the tank. A healthy tank sounds hollow at the top. A tank that sounds full all the way up has lost its air.
2. Check the air charge. Power off, drain the system to zero, and read the air valve on top of the tank with a tire gauge. It should sit about 2 psi below the cut-in pressure (38 psi for a 40/60 switch, 28 psi for 30/50).
3. Recharge and watch. Add air with a compressor, restore power and see if cycling stops. If the tank loses air again within days, or water spits from the air valve, the diaphragm or bladder has failed and the tank needs replacing.
4. Rule out leaks and the check valve. If pressure drops with every tap closed, look for a running toilet or a leak. If there's none, a check valve may be leaking back into the well.

Step-by-step: breaker or overload trips

A trip that repeats is the pump system telling you something is wrong. The usual causes, in the order pros check them:

• Voltage outside about plus or minus 10% of the motor rating, often from a loose connection or long cable run.
• Heat: a control box in direct sun or a hot room. The box shouldn't be hot to the touch.
• A failing control box, especially an old one.
• Corroded splices at the wellhead, where the wire enters the house, or at the motor.
• A stalled or failing motor. Amp draw several times normal points to a bound pump.

Checking amps and voltage under load is safe with a clamp meter if you know the basics. Anything past that, call a licensed pump contractor.

Low well water or a pump running dry

If the pump runs, sputters, then pushes air or sand, the water level may be falling to the pump intake. This happens in droughts, during long irrigation runs, or as a well's yield drops. Shut the pump off and let the well recover. A pro can measure static and pumping levels, lower the pump if there's room, or add dry-run protection. Some constant-pressure pumps, such as the Grundfos SQE, have this protection built in.

When to call a pro

• Anything that requires pulling the pump, opening the well cap seal or working on the pitless adapter
• Repeated breaker trips, burned wiring or a hot control box
• Air, sand or muddy water at the taps
• A pump that runs nonstop with no leaks you can find
• Any time you aren't comfortable working around 240V

Ask the contractor for the readings they take: voltage, amps, and insulation resistance. Those numbers tell you whether the pump really needs replacing.

After any repair

Opening the well or plumbing can let bacteria in. After work inside the well, shock-chlorinate and test for coliform bacteria before drinking the water again. If tests keep coming back positive, see our guide to bacteria in well water and whether UV treatment fits. If sand or grit showed up during the problem, a spin-down sediment filter protects your fixtures and any whole-house filter downstream.

Mistakes to avoid

• Replacing the pump first. Switches, tanks and control boxes fail far more cheaply. Check them before paying to pull a pump.
• Setting tank air with water in the tank. The reading is meaningless unless the system is drained to zero.
• Swapping a control box that doesn't match. The box must match the motor's brand, horsepower and voltage.
• Turning up the pressure switch to fix low pressure. It can push a worn pump past its limit and leave it running nonstop.
• Ignoring short cycling. Every start heats the motor and wears the switch contacts.