A well pump that won't shut off is almost always fighting a waterlogged pressure tank, a failing pressure switch, a leak somewhere in the system, or a well that's running low on water. The fix depends entirely on which one it is, but the first move is the same in every case: if the pump has been running for more than a few minutes straight with no sign of stopping, cut power at the breaker to protect the motor while you figure out the cause. None of the common causes are true 24/7 emergencies the moment you notice them, but none of them get better on their own either. Here's how to tell what's happening and what it actually takes to fix it.
What Does It Mean When a Well Pump Won't Shut Off?
A normal well pump runs in short cycles. It kicks on when pressure in the tank drops to a set point, pushes water until the tank refills to a higher pressure, and then shuts off and rests until the next cycle starts. Most residential systems cycle on for a minute or two at a time and then sit idle for a while, sometimes a long while, depending on how much water the house is using.
A pump that won't shut off breaks that pattern in the opposite direction from short cycling. Instead of clicking on and off every few seconds, it just keeps running, sometimes for many minutes, sometimes for hours, without ever reaching the pressure it needs to shut off. You might notice water pressure that never quite feels right, a pump that's audibly running nonstop in the background, or an electric bill that jumps for no obvious reason. This is a different symptom from a well pump that isn't working at all, where the problem is no pump activity and no water. Here the pump is very much working, it just can't tell itself when to stop.
Austin Drilling's own team sees this exact call regularly enough that it's one of the named symptoms on our well problems page: a pump running constantly is usually fighting a pressure tank problem, a leak in the line, or low water in the well. All three of those point back to the same underlying issue, which is that something in the system is preventing the pump from ever reaching its normal cutoff pressure.
What Causes a Well Pump to Run Constantly?
The pump itself is rarely the actual problem when it won't shut off. In most cases it's doing exactly what it's built to do, which is run until pressure builds high enough to trigger the cutoff switch, and something else in the system is stopping that pressure from ever building.
A waterlogged pressure tank is the most common culprit. The tank holds a cushion of compressed air above the water inside it, and that cushion is what lets the tank hold pressure and signal the pump to stop. When the tank's internal bladder tears or the air charge slowly leaks away over months or years, the tank can no longer hold pressure on its own, so the pump keeps running to try to compensate and never gets there.
A handful of other issues produce the same symptom, and a homeowner usually can't tell them apart just by listening to the pump:
- A worn or miscalibrated pressure switch that never registers the cutoff pressure
- A leak anywhere in the system, from a running toilet to a cracked underground line
- A well that's drawing down faster than it recharges, so the pump can't build pressure against a falling water level
- A stuck or failed check valve that lets water drain backward into the well between cycles
- A pump that's undersized for the household's actual demand and simply can't keep up
A leak is worth ruling out first, because it's the cheapest possible cause and the easiest to miss. A single running toilet or a dripping outdoor spigot can create just enough constant demand to keep the pump firing nonstop, and it has nothing to do with the well or the pump at all. Walk the house and check every fixture, and if you have an irrigation well or a separate outdoor line, check those valves too before assuming the problem is buried underground. If every fixture is off and the pump is still running, the cause is somewhere in the well system itself, and that's where a pressure tank, a pressure switch, or the well's own water level come into play.
Is It Dangerous to Let a Well Pump Keep Running?
Not in the sense of an immediate safety threat to your home, but it is genuinely dangerous to the pump itself, and that matters because a submersible pump replacement is one of the more expensive repairs a well system needs. A pump that runs continuously without ever reaching its cutoff pressure is working far harder than it was designed to, and the motor generates heat the whole time it runs. If the well's water level has actually dropped below the pump's intake, the danger gets worse fast: a pump running dry, meaning it's spinning without water to cool and lubricate it, can burn out its motor within minutes rather than hours.
That's the real reason to cut power at the breaker if the pump has been running continuously for more than a few minutes with no faucet open anywhere in the house. It costs you nothing to shut it off and check things over, and it can be the difference between a pressure switch repair that costs a couple hundred dollars and a full pump replacement that costs thousands. If you hear grinding, a burning smell, or the pump suddenly goes silent after running hard, that's your signal to leave the power off and call rather than experiment further.
How Is This Different From a Pump That Short Cycles?
These two symptoms get confused constantly because they're both pressure tank problems at their core, but they show up in opposite ways. Short cycling means the pump clicks on and off rapidly, sometimes every few seconds, dozens of times an hour. A pump that won't shut off does the opposite: it starts and then simply never reaches the pressure needed to stop, running continuously instead of cycling at all.
The overlap is that a waterlogged pressure tank can actually cause either pattern depending on exactly how it's failing and how the house is using water at the time, which is part of why both symptoms trace back to the same handful of causes. If your pump is clicking on and off in rapid bursts rather than running steadily without stopping, you're dealing with the cycling pattern instead, which has its own separate causes and fixes. Either way, the diagnostic starting point is the same pressure tank and pressure switch, so don't worry too much about naming the symptom precisely before you call; a technician will identify which pattern you actually have within minutes.
What Should You Do Right Now?
If your well pump has been running continuously for several minutes and no water is running anywhere in the house, start here. First, check every faucet, toilet, and outdoor spigot to rule out something simple like a toilet flapper that's stuck open, since that alone can keep a pump running indefinitely. Second, if everything is off and the pump is still running, go to your breaker panel and shut off power to the well pump. This protects the motor from continuing to run under strain while you sort out the actual cause, and it's completely reversible if it turns out to be a simple fix.
Third, once power is off, take a look at your pressure tank if you know where it is. A tank that feels warm, is dripping, or shows an obviously torn or bulging spot is telling you something useful. You don't need to open anything or touch the pressure switch itself; that part is not a homeowner task. Fourth, call a well professional and describe exactly what you saw and heard, including how long the pump ran before you shut it off and whether you noticed any unusual sounds. That detail helps a technician arrive with the right parts on the truck instead of making a second trip.
What Does It Cost to Fix a Well Pump That Won't Shut Off in South Carolina?
Costs vary widely because the fix depends entirely on which component actually failed, and a good technician diagnoses that before quoting you anything rather than guessing at parts.
| Repair | Typical cost range |
|---|---|
| Diagnostic visit | $100 - $300 |
| Pressure switch replacement (professional) | $150 - $300 |
| Pressure tank replacement, installed | $350 - $700 |
| Check valve replacement | $400 - $800 |
| Well yield or leak testing | $200 - $500 |
| Pump replacement | $500 - $2,500 |
A pressure switch is the cheapest of the common fixes and often the fastest, while a full pump replacement sits at the top end because it involves pulling the existing pump out of the well casing and setting a new one. These are typical ranges, not a quote for your specific well; well depth, pump type, and how the parts are actually failing all move the number, and the only way to know your real cost is to have someone look at the tank, the switch, and the pump in person.
Should You Try to Fix This Yourself or Call a Professional?
Checking every fixture in the house for something left running is completely safe to do yourself, and it solves the problem outright often enough that it's always worth doing first. Cutting power at the breaker is also safe and something every well owner should know how to do. Beyond those two steps, this becomes a call-a-professional situation.
Opening a pressure switch, testing a well's water level, or pulling a pump out of the casing all require training and the right equipment, and getting any of them wrong risks a real shock or a pump that's damaged worse than it already was. We'd rather a homeowner call us for the diagnosis than open a pressure switch to look, since the parts inside carry enough current to genuinely hurt someone who doesn't do this for a living. A same-day diagnostic during business hours is also almost always the more affordable path compared to letting the problem run unattended until something fails outright on a weekend.
How Does Austin Drilling Fix a Well Pump That Won't Shut Off?
Austin Drilling has been fixing well problems across the Midlands and Upstate for 66 years, and a pump that won't shut off is one of the calls our technicians handle most often, right alongside its opposite symptom, short cycling. We start with an actual diagnostic visit: checking your pressure tank's condition and air charge, testing the pressure switch's settings, and confirming the well's static water level so we know whether the pump is genuinely running dry or fighting a tank or switch problem instead.
Every pump and pressure tank we install through our pump services goes through a full system assessment first, so the equipment matches your household's real demand rather than whatever happened to be on the truck. That matters here specifically, because an undersized pump strains constantly trying to keep up with demand and burns out early, which can look a lot like this exact symptom. Every installation carries a 5-year manufacturer's warranty on the pump and pressure tank, plus a full year-one service guarantee: if anything goes wrong in that first year, we come back and fix it at no charge, aside from acts of nature like lightning or a hard freeze.
How Can You Prevent This From Happening Again?
A yearly check of your pressure tank's air charge is the single best habit here, the same maintenance step that helps prevent the opposite symptom of short cycling. A tank that's slowly losing its air cushion over months eventually can't hold pressure at all, and catching that early with a quick top-off is far cheaper than waiting for the tank to fail outright.
It also helps to walk the house periodically for small leaks that add up. A toilet flapper that doesn't fully seal, a hose bib left slightly open, or an irrigation zone that doesn't close all the way can each create enough constant demand to keep a pump running far more than it should, and none of them are obvious unless you're specifically looking. If your property has an irrigation well or a separate outdoor system, check those valves on the same schedule, since a leak out in the yard is just as hard on a pump as one under the kitchen sink.
Finally, pay attention to how your well performs during dry stretches. A well that's genuinely running low on water during a drought can produce this same symptom, and if it happens every summer or during extended dry periods, that's worth a conversation about your well's actual yield rather than treating it as a one-time pressure tank problem.
Frequently Asked Questions
Why does my well pump keep running and never shut off?
Most often it's a waterlogged pressure tank that's lost its air charge, a worn pressure switch that never registers the cutoff pressure, a leak somewhere in the house or yard, or a well that's running low on water. All four produce the same basic symptom of a pump that never reaches the pressure it needs to stop.
Is it bad to let a well pump run constantly?
Yes, because the motor generates heat the entire time it runs, and if the well's water level has dropped below the pump's intake, the pump can run dry and burn out its motor within minutes rather than hours. Cutting power at the breaker while you sort out the cause protects the equipment and costs you nothing.
Can a bad pressure switch cause a well pump to run nonstop?
Yes, a pressure switch that's worn or miscalibrated can fail to sense that the tank has reached cutoff pressure, so it never signals the pump to stop even though the tank is actually full. This is one of the more affordable fixes on this list once it's confirmed.
How do I know if my pressure tank is waterlogged?
A tank that feels unusually heavy, has lost its air cushion, or shows a torn or bulging bladder is typically waterlogged. A technician can confirm it quickly by checking the tank's air charge with a pressure gauge, which is a fast, non-invasive test.
What's the difference between a well pump that won't shut off and one that short cycles?
A pump that won't shut off runs continuously without stopping. A short-cycling pump does the opposite, clicking on and off rapidly in bursts of just a few seconds. Both usually trace back to the same pressure tank or switch, but the pattern you're hearing tells a technician which direction to start diagnosing from.
Should I turn off the breaker if my well pump won't stop running?
Yes, if you've checked every fixture in the house and confirmed nothing is running, shutting off power at the breaker protects the motor while you arrange for a diagnostic visit. It's fully reversible and takes seconds to do.
Get Your Well Pump Running Normally Again
A well pump that won't shut off is rarely an emergency in the first few minutes, but it becomes an expensive one the longer it runs unattended, especially if the well itself is running low on water. Check every fixture in the house first, cut power at the breaker if the pump keeps running with nothing open, and give us a call from there. Austin Drilling's technicians handle this exact call across West Columbia, Newberry, and the surrounding Midlands and Upstate every week.
Call West Columbia at (803) 926-5402 or Newberry at (803) 926-7080, Monday through Friday from 7am to 6pm, with Saturday appointments available, or find your nearest office on our contact page. We'll check your pressure tank, your switch, and your well's water level, tell you honestly what's actually wrong, and get your pump back to running the way it should.
Talk to a Real Well Company
66 years, 13,000+ wells, in-house crews across the SC Midlands and Upstate. Call Austin Drilling and we'll get your water right.