Well Pump Cycles On Without Water Use? Find the Leak

Why This Happens

How Your System Works

• Pump fills pressure tank
• Pressure reaches cut-out (e.g., 60 PSI)
• Pump shuts off
• Tank holds pressure when no water is used
• Pump should stay off until you use water

What's Happening

• Pressure is dropping even when nothing's running
• When pressure drops to cut-in (e.g., 40 PSI)
• Pump turns on to restore pressure
• This shouldn't happen unless water is leaving the system

The Problem

Water is going somewhere—either leaking out of the system, or draining back into the well (check valve failure).

Finding the Leak

Step 1: Confirm the Problem

1. Make sure all water is off (faucets, appliances, irrigation)
2. Watch pressure gauge on tank
3. If pressure drops over 5-10 minutes, you have a leak
4. How fast it drops indicates leak size

Step 2: Check Toilets First

Toilets are the #1 cause of phantom cycling.

• Put food coloring in toilet tank
• Wait 15-30 minutes (don't flush)
• If color appears in bowl, flapper is leaking
• Check all toilets

Step 3: Listen and Look

• Listen for running water (at night is easiest)
• Check under sinks for drips
• Inspect visible pipes
• Look for wet spots on walls, ceilings, floors
• Check outdoor faucets and irrigation

Step 4: Isolate Sections

• Close main valve to house
• Watch pressure gauge
• If pressure still drops = leak is between well and valve
• If pressure holds = leak is inside house

Step 5: Check the Check Valve

• If no visible leak anywhere
• Water may be draining back into well
• Failed check valve allows backflow
• Requires professional to diagnose/replace

Common Causes

1. Running Toilet (Most Common)

• Flapper valve not sealing
• Fill valve stuck open
• Float adjusted wrong
• Can waste 200+ gallons per day

2. Dripping Faucets

• Single drip = 5+ gallons/day
• Multiple faucets add up
• May not seem like much but causes cycling

3. Leaking Pipe

• Underground leak (hard to find)
• Pipe in wall or crawlspace
• Joint or fitting failure
• May see wet spots or hear water

4. Failed Check Valve

• No visible leak
• Water drains back into well
• Pressure drops when pump off
• Need to pull pump to replace

5. Pressure Tank Issue

• Waterlogged tank = rapid cycling
• Tank bladder may be leaking
• Low air charge
• Different from system leak but similar symptoms

6. Irrigation Leak

• Broken sprinkler head
• Valve stuck open
• Underground irrigation line break
• Check even when system "off"

7. Water Heater Issues

• T&P valve dripping
• Drain valve leaking
• Tank itself leaking

Fixes

Toilet Repairs

• Replace flapper: $5-$15 (DIY)
• Replace fill valve: $10-$25 (DIY)
• Or replace entire mechanism: $15-$30
• Easy DIY fix

Faucet Repairs

• Replace washers or cartridge
• Parts: $10-$50
• Often DIY-able

Pipe Leaks

• Depends on location and severity
• Visible pipe repair: $100-$300
• Underground leak: $500-$2,000+
• May need professional plumber

Check Valve Replacement

• Requires pulling pump (submersible)
• Cost: $500-$1,500
• Professional service

Pressure Tank

• Recharge air if low
• Replace if bladder failed
• Cost: $300-$800 for replacement

Why It Matters

Wasted Water

• Even small leaks add up
• Toilet leak: 200+ gallons/day
• For wells, less concern about bills but...

Pump Wear

• More cycles = more wear
• Shortens pump life
• Increases energy use

Bigger Problems

• Small pipe leak becomes big leak
• Water damage potential
• Better to find early

We service all major pump brands including Franklin Electric, Grundfos, Goulds (Xylem), and Sta-Rite (Pentair). Our trucks carry common parts and components for same-day repairs.

Frequently Asked Questions

Why does my well pump turn on when no water is being used?

Pressure is dropping from a leak. Check toilets first (most common), then faucets, pipes, and check valve.

How do I find a hidden water leak?

Watch pressure gauge with all water off. Test toilets with food coloring. Listen for running water. Isolate sections by closing valves.

Could it be the pressure tank instead of a leak?

Yes—waterlogged tank causes rapid cycling. But tank issues typically cause very fast cycling, while leaks cause periodic cycling.

What if I can't find the leak?

May be underground, in wall, or check valve failure (water goes back into well). Professional leak detection may be needed.

Is a running toilet that serious?

Yes! Can waste 200+ gallons/day, causes constant pump cycling, and wears out your pump faster. Fix it promptly.