A well pump that won't shut off is failing to reach its cut-off pressure (usually 60 psi), and there are only three reasons: water is escaping somewhere, the pump can't build pressure anymore, or the pressure switch is broken. This is a same-day problem — a pump running around the clock is burning electricity, overheating, and if the well level has dropped, destroying itself. Here's the gauge-first diagnosis.
Step 0: Protect the pump while you think
If you can't troubleshoot right now, flip the pump's breaker off and treat water like a camping trip — turning it on briefly when needed. Hours of dry-running can end a $1,200–$3,500 submersible; the breaker is free.
Read the gauge — it names the suspect
| Gauge behavior (pump running) | What it means | Prime suspect |
|---|---|---|
| Climbs past cut-off (60+ psi), pump still on | Switch isn't reacting | Failed/stuck pressure switch ($25–$50) |
| Plateaus below cut-off (e.g. 45 psi) and sits | Water out = water in | Leak somewhere in the system |
| Climbs slowly, barely moves | Pump can't produce | Worn pump, dropped water level, or broken drop pipe |
| Won't climb at all, sputtering taps | Pump moving air | Well level at pump intake — stop the pump NOW |
Hunting the leak (the most common branch)
- Toilets first: food coloring in every tank; color in the bowl in 15 minutes = your 200-gallon-a-day thief. Cheapest fix on the list.
- Everything visible: softener stuck in regeneration, dripping relief valves, hose bibs, irrigation left on, livestock waterers.
- The buried service line: unexplained wet or lush stripes between wellhead and house (not to be confused with drainfield stripes).
- Inside the well — the check valve or drop pipe: if the pump cycles or runs with zero water use and the house side is tight, water may be draining back down the well through a failed check valve or a split drop pipe. That's a pull-the-pump diagnosis — pro territory, priced in our pump guide.
- Rule out the tank while you're there: a waterlogged pressure tank causes rapid cycling more than continuous running, but its air-charge check takes two minutes and eliminates a variable.
When it's the pump or the well itself
A pump that runs long but pressure creeps ever slower — especially in drought, late summer, or heavy-use evenings — may be telling you about the well, not the plumbing: a dropping water level or aging pump losing capacity. Run the capacity math, review the pump-failure symptoms, and if the well is the question, get a water-level measurement before anyone quotes new drilling.
Frequently Asked Questions
Why does my well pump keep running and never shut off?
The pump shuts off when system pressure reaches the cut-off setting (usually 60 psi) — so continuous running means it can't get there. The three causes: water is escaping somewhere (a leak, running toilet, or failed check valve), the pump can't build pressure anymore (worn pump or dropping water level), or the pressure switch itself has failed. The gauge tells you which.
Is it bad if the well pump runs constantly?
Yes — urgently so. A continuously running pump overheats, burns electricity around the clock, and if the well level has dropped, can run dry — which destroys a $1,200–$3,500 submersible in hours. If you can't diagnose it the same day, switch the pump breaker off between uses to protect it.
How do I know if my pressure switch is bad?
With the pump running, watch the gauge: pressure climbing past the cut-off without the pump stopping points at the switch (stuck contacts or a clogged sensor tube); pressure plateauing below cut-off means the water is going somewhere or the pump is done. A pressure switch is a $25–$50 part — always the hopeful diagnosis.
Can a running toilet make a well pump run constantly?
Absolutely — it's the most common and cheapest culprit. A silently running toilet can pass 200+ gallons a day, enough to keep pressure from ever reaching cut-off. Put food coloring in every tank; color in a bowl within 15 minutes without flushing = found it. (Your septic drainfield will thank you too.)