Why Your Well Pump Won't Shut Off
Experiencing this problem right now? Call us for immediate assistance.
A well pump that runs forever—never reaching cutoff pressure—is working overtime and wearing out fast. Your electric bill climbs while the pump heads toward failure. The good news: the causes are identifiable, and most are fixable without replacing the pump.
Common Causes (In Order of Likelihood)
1. Waterlogged Pressure Tank (Most Common)
The pressure tank contains an air bladder that compresses when water enters. Over time, this bladder can fail, filling the tank entirely with water. Without the air cushion, the pump can never build enough pressure to reach the cutoff point. Signs: Tank feels heavy, water spurts from air valve when pressed, pump cycles very rapidly when working properly.
2. Water Leak in System
Even a small leak constantly drains pressure. The pump tries to maintain pressure but can't keep up with the loss. Common leak locations:
- Underground supply line to house
- Toilet fill valve (running toilet)
- Outdoor faucet or irrigation system
- Water heater T&P valve
- Worn faucet washers
- Humidifier or water softener drain line
3. Failed Pressure Switch
The pressure switch tells the pump when to start and stop based on system pressure. If the switch contacts weld together (from arcing) or get stuck closed from corrosion, they'll keep sending power regardless of pressure. Signs: Burned or pitted contacts visible when cover is removed, switch body feels hot.
4. Pressure Settings Too High
If someone adjusted the pressure switch cutoff higher than the pump can achieve, it will run forever trying to reach an impossible target. Most residential pumps max out at 60-70 PSI. If cutoff is set to 80 PSI, the pump will never reach it.
5. Declining Pump Performance
Worn pump impellers, clogged intake screens, or a dropping well water level can reduce pump output. A pump that once easily reached 60 PSI may now max out at 45 PSI—not enough to trigger a 50 PSI cutoff. Signs: Gradual decline in water pressure over months/years.
6. Check Valve Failure
The check valve prevents water from draining back into the well when the pump stops. A failed check valve lets water flow backward, causing the pump to lose prime and struggle to rebuild pressure.
Warning Signs to Watch For
- Pump runs continuously without cycling off
- Pressure gauge shows lower than cutoff pressure
- Electric meter spinning faster than normal
- Pump or motor feels hot
- Can hear pump running at all hours
How to Diagnose and Fix This Problem
Step 1: Turn Off the Pump Immediately
Continuous running damages the pump through overheating. Turn off the breaker feeding the pump (usually labeled "well" or "pump"). This stops the damage while you diagnose.
Step 2: Check the Pressure Gauge
Note the pressure reading. If it's well below normal (say, 25 PSI when it should be 50), the pump is struggling to build pressure. If it's at or near normal, the issue is likely the switch not recognizing the pressure.
Step 3: Check for Running Water Inside
Walk through the house checking every fixture:
- Toilets: Listen for running water. Remove tank lid and watch if water is flowing.
- Faucets: Make sure all are fully closed.
- Water heater: Check the T&P relief valve and drain pan.
- Appliances: Check washing machine, dishwasher, refrigerator ice maker.
Step 4: Check Outdoor/Underground
- Verify all outdoor faucets are closed
- Turn off irrigation system at controller AND any manual valves
- Walk the route of buried water lines looking for wet spots or unusually green grass
- Check any outbuildings, barns, or guest houses
Step 5: Test the Pressure Tank
With power still off and pressure released:
- Locate the air valve (like a tire valve) on top of tank
- Press it briefly
- If water sprays out, the bladder has failed—tank needs replacement
- If only air comes out, check the air pressure with a tire gauge (should be 2 PSI below cut-in pressure)
Step 6: Inspect the Pressure Switch
With power OFF:
- Remove the cover (usually a plastic cap)
- Look at the contacts—are they burned, pitted, or fused together?
- Check for signs of overheating (melted plastic, burn marks)
- Gently tap the switch housing while observing contacts
A failed switch costs $20-$50 to replace yourself, or $75-$150 with labor.
Step 7: Isolate the Well System
Close the shutoff valve right after the pressure tank. Turn on the pump briefly. If pressure builds and holds, the leak is downstream (in the house). If it still won't build pressure, the problem is the well, pump, or check valve.
Cost to Fix Common Causes
| Problem | DIY Cost | Professional Cost |
|---|---|---|
| Pressure switch replacement | $20-$50 | $75-$150 |
| Pressure tank replacement | $150-$400 | $300-$800 |
| Toilet fill valve replacement | $15-$30 | $75-$150 |
| Check valve replacement | $50-$100 | $150-$300 |
| Underground leak repair | N/A | $500-$2,000+ |
| Well pump replacement | N/A | $1,500-$3,500 |
When to Call a Professional
While some minor issues can be addressed by homeowners, well system problems often require professional diagnosis. Call Southern California Well Service if:
- You're not comfortable working with electrical systems
- The problem persists after basic troubleshooting
- You notice multiple symptoms at once
- Your well is over 10 years old and hasn't been serviced
We offer same-day emergency service throughout San Diego, Riverside, and San Bernardino counties.
Frequently Asked Questions
Will a well pump burn out if it runs constantly?
Yes, eventually. Continuous running causes overheating and accelerates wear. Address the problem immediately to prevent pump failure.
How do I stop my well pump from running constantly?
Find and fix the cause—usually a waterlogged tank, leak, or pressure switch problem. Don't just let it run hoping it will fix itself.
Can a stuck pressure switch cause pump to run continuously?
Absolutely. If the switch contacts weld together or stick closed, they'll keep sending power regardless of pressure.
How much electricity does a constantly running well pump use?
Most well pumps use 1-5 kW per hour. Running 24/7 adds $100-300+ monthly to your electric bill.
Need Help Now?
Southern California Well Service provides expert well pump repair and diagnostics. We've been solving well problems across Southern California since 2006.
Call (760) 440-8520 for ServiceRelated Articles
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