By SCWS Team
February 2, 2026 · 11 min read
Click... click... click... click. That's the sound of your well pump turning on and off every few seconds—a condition called short cycling—and it's one of the most damaging things that can happen to your well system. Every rapid cycle puts stress on the pump motor, overheats components, and brings your pump closer to complete failure. If your pump is short cycling, this is an urgent problem that needs immediate attention.
🚨 Urgent Warning
A well pump that's short cycling can burn out in weeks or even days—turning a $300-$800 pressure tank replacement into a $1,500-$3,500+ pump replacement. Don't ignore this problem.
What Is Well Pump Short Cycling?
A healthy well pump should turn on, run for 1-2 minutes while filling the pressure tank, then shut off and stay off until enough water is used to drop the pressure. The tank acts as a buffer, storing pressurized water so the pump doesn't have to run every time you turn on a faucet.
Short cycling is when the pump turns on and off far too frequently—sometimes every few seconds. Instead of smooth, steady water delivery, you get:
- Pump clicking on and off rapidly while water is running
- Pressure gauge needle bouncing up and down
- Fluctuating water pressure at fixtures
- Electrical noise or clicking from the pressure switch area
- Unusually high electricity bills
The 5 Causes of Well Pump Short Cycling
1. Waterlogged Pressure Tank (Most Common)
Your pressure tank contains an internal rubber bladder that separates air from water. The air compresses and expands to maintain consistent pressure without the pump running constantly. When this bladder fails or loses its air charge, the tank fills completely with water—it becomes "waterlogged."
A waterlogged tank can only hold a tiny amount of water before pressure drops and triggers the pump. Result: the pump cycles constantly.
Signs of a waterlogged tank:
- Tank sounds solid when tapped (no hollow sound at top)
- Water sprays out when you press the air valve
- Tank feels cold and heavy all over
- Problem developed gradually over months/years
đź’ˇ Quick Test
Turn off the pump, open a faucet to release pressure, then press the Schrader valve on top of the tank. If water sprays out instead of air, your bladder has failed and the tank needs replacement.
Fix: If the bladder is intact but undercharged, adding air may solve the problem. If the bladder has failed, the tank must be replaced. Pressure tank replacement typically costs $300-$800 including labor.
2. Failing Pressure Switch
The pressure switch tells the pump when to turn on (at low pressure) and off (at high pressure). When the switch contacts become worn, burned, or corroded, it may not read pressure correctly, triggering the pump at the wrong times.
Signs of pressure switch problems:
- Clicking sounds from the switch itself
- Visible corrosion or burn marks on contacts
- Cut-in and cut-out points have shifted
- Pump cycles even when pressure gauge shows normal
Fix: Pressure switch replacement is relatively simple and costs $150-$300 including parts and labor. If you're comfortable with electrical work, this can be a DIY repair.
3. Water Leak in the System
If water is escaping somewhere—a running toilet, leaking pipe, dripping irrigation valve, or underground leak—the system constantly loses pressure, triggering the pump repeatedly. The leak might be obvious or completely hidden.
Signs of a leak:
- Pump cycles even when no water is being used inside
- Wet spots in yard or near well
- Running toilets or dripping faucets
- Water meter (if present) shows usage with everything off
- Higher than expected water usage
How to test: Turn off all water use in the house. Watch the pressure gauge—if pressure drops while nothing is running, you have a leak somewhere.
Fix: Find and repair the leak. This can range from a simple toilet flapper replacement to professional leak detection for underground issues.
4. Failing Check Valve
The check valve prevents water from draining back into the well when the pump shuts off. If it's failing, water runs backward, pressure drops, and the pump turns back on immediately.
Signs of check valve failure:
- Pump runs briefly right after shutting off
- Pressure drops rapidly after pump cycles
- Air sputtering at faucets (related issue)
- Pump takes longer to build pressure
Fix: Check valve replacement costs $200-$500 depending on whether it's at the pressure tank (easy) or down in the well (requires pulling the pump).
5. Undersized or Failing Pump
Less commonly, the pump itself may be the problem. An undersized pump struggles to maintain pressure, while a worn pump loses efficiency over time. In both cases, the pump can't keep up with demand, leading to pressure fluctuations that trigger short cycling.
Signs of pump issues:
- Problem started after new fixtures or irrigation added
- Overall water pressure has decreased over time
- Pump is 10+ years old
- Short cycling accompanied by weak flow
Fix: Pump replacement costs $1,500-$3,500 or more depending on well depth and pump size.
Why Short Cycling Is So Damaging
You might wonder: if the pump is turning on and off, at least it's still working, right? Unfortunately, short cycling is one of the worst things that can happen to a well pump:
"A pump designed to last 15 years can burn out in weeks if it's short cycling. Every rapid start puts enormous stress on the motor—it's like repeatedly slamming on your car's brakes and gas pedal simultaneously."
The Hidden Damage of Short Cycling
- Motor overheating: Pumps are cooled by the water flowing past them. Constant starting generates heat faster than it can dissipate.
- Electrical stress: Starting a pump motor draws 5-7 times more current than running it. Frequent starts burn out windings and capacitors.
- Mechanical wear: Bearings and seals wear out exponentially faster with rapid cycling.
- Energy waste: You're paying for all those start-up power surges. Electricity bills can double or triple.
- Pressure switch damage: The switch contacts arc and burn with each cycle, compounding the problem.
How to Diagnose Short Cycling
Use this systematic approach to identify the cause:
Step-by-Step Diagnosis
- Check for obvious leaks: Inspect toilets, faucets, and visible plumbing. Listen for running water.
- Test for hidden leaks: With all water off, watch the pressure gauge. If pressure drops, you have a leak.
- Inspect the pressure tank: Tap on it—should sound hollow at top. Check air valve for water.
- Check tank air pressure: With pump off and pressure released, air pressure should be 2 PSI below cut-in (typically 28-38 PSI).
- Examine the pressure switch: Look for corrosion, burned contacts, or loose wires.
- Watch the pressure gauge: Does pressure build steadily when pump runs? Erratic readings suggest problems.
DIY Fixes You Can Try
Recharge the Pressure Tank
If the bladder is intact but undercharged:
- Turn off the well pump at the breaker
- Open a faucet to drain all water from the tank
- Check air pressure at the tank's Schrader valve
- Add air with a bicycle pump or compressor to 2 PSI below your cut-in pressure
- Close the faucet and turn the pump back on
- Monitor for proper cycling (should run 1-2 minutes, then off for several minutes)
Fix Obvious Leaks
Running toilets and dripping faucets are common culprits. Replace worn toilet flappers, tighten loose fittings, and repair any visible leaks.
Adjust or Replace Pressure Switch
If you're comfortable with electrical work:
- Turn off power at the breaker
- Remove the pressure switch cover
- Inspect contacts for burning or pitting
- Clean contacts with fine sandpaper or emery cloth
- Check that adjustment nuts haven't loosened
- If contacts are badly damaged, replace the switch ($30-$60 for parts)
⚡ Safety Warning
Well pumps run on 240-volt electricity. Always turn off power at the breaker before working on electrical components. If you're not completely comfortable with electrical work, call a professional—the savings aren't worth the risk.
When to Call a Professional
Get professional help if:
- DIY fixes don't work—the problem requires deeper diagnosis
- Pressure tank needs replacement—involves plumbing and potentially electrical work
- Check valve issues—especially if the valve is down in the well
- Suspected pump problems—requires pulling the pump from the well
- Underground leaks—need professional leak detection equipment
- You're uncomfortable with the diagnosis—better safe than sorry
Learn more about our well pump repair services or preventive maintenance programs.
How SCWS Handles Short Cycling Problems
When you call Southern California Well Service for a short cycling problem, here's what to expect:
- System inspection: We check the pressure tank, pressure switch, and all accessible components
- Pressure testing: We verify proper cut-in and cut-out pressures
- Tank diagnosis: We determine if the tank can be recharged or needs replacement
- Leak detection: We test for hidden leaks in the system
- Clear explanation: We explain what we found and your repair options
- Same-day repair: Most short cycling problems can be fixed the same day
Frequently Asked Questions
Why does my well pump turn on and off every few seconds?
A well pump cycling on and off rapidly (short cycling) is almost always caused by a waterlogged pressure tank. When the air bladder in your tank fails, the tank fills with water and can only store a tiny amount before pressure drops and triggers the pump again. Other causes include a failing pressure switch, leaks in the system, or an undersized pressure tank.
Is short cycling bad for my well pump?
Yes, short cycling is extremely damaging to your well pump. Pumps are designed to run for 1-2 minutes, then rest and cool down. Rapid cycling causes motor overheating, premature wear on electrical components, and can reduce a pump's lifespan from 10-15 years to just months. It also dramatically increases your electricity bills.
How do I know if my pressure tank is waterlogged?
To test for a waterlogged pressure tank: turn off the pump and drain some water from the system. Tap on the tank from top to bottom—a healthy tank sounds hollow at the top (air) and solid at the bottom (water). A waterlogged tank sounds solid throughout. You can also check the air valve at the top; if water sprays out, the bladder has failed.
Can I fix short cycling myself?
Some causes of short cycling are DIY-fixable: if the pressure tank bladder is intact, you may just need to add air. Check the air pressure at the tank valve (should be 2 PSI below cut-in pressure). However, if the bladder has failed, the tank needs professional replacement. Pressure switch issues and system leaks may also require professional diagnosis.
How much does it cost to fix well pump short cycling?
Repair costs depend on the cause: recharging a pressure tank is often free (DIY) or $100-$200 for a service call. Pressure tank replacement costs $300-$800 including labor. Pressure switch replacement runs $150-$300. If short cycling has already damaged your pump, replacement costs $1,500-$3,500 or more depending on well depth.
Stop the Clicking—Save Your Pump
Every click of that rapidly cycling pump is money and lifespan draining away. The good news: most short cycling problems are caused by the pressure tank, which is one of the less expensive components to repair or replace. But wait too long, and you'll be replacing the pump too.
Don't let a $300-$800 tank problem become a $3,500+ pump replacement. Call us today for fast, professional diagnosis and repair.
Stop Short Cycling Before It Destroys Your Pump
Our technicians diagnose and repair short cycling problems throughout San Diego County—often the same day you call. We'll find the cause, explain your options, and get your system running properly before real damage is done.
