Well Pump Runs When No Water Used? Find the Leak

Why This Happens

How the System Works

• Pump builds pressure in the tank
• Pump shuts off at cut-out pressure (e.g., 50 PSI)
• When pressure drops to cut-in (e.g., 30 PSI), pump starts
• If pressure drops with no water use = leak

Where Water Can Go

• Visible leak (faucet, toilet, fixture)
• Hidden leak (pipe in wall, underground)
• Back down the well (bad check valve)
• Out of pressure tank (failed bladder)

The Cost of Ignoring

• Pump runs excessively = shorter life
• Higher electric bills
• Water wasted
• Potential water damage from leak

Check Inside First

Toilets (Most Common Culprit)

Running toilets waste huge amounts of water and are often silent.

The Dye Test:

1. Put food coloring in toilet tank
2. Don't flush
3. Wait 15-20 minutes
4. Check bowl—if color appears, flapper is leaking
5. Test ALL toilets

What to Fix:

• Replace flapper ($5-$15)
• Adjust fill valve if running
• Replace entire flush mechanism if needed

Faucets

• Any dripping faucet = water loss
• Check all sinks, tubs, showers
• Even slow drips add up

Water Heater

• Check pressure relief valve
• Look for puddles
• Check drain valve

Appliances

• Dishwasher
• Washing machine hoses
• Ice maker line
• Water softener

Check Outside

Hose Bibs

• Faucets fully closed?
• Hoses disconnected or turned off?
• Frost-free faucets leaking inside wall?

Irrigation System

• Stuck valve running constantly?
• Broken sprinkler head?
• Cracked pipe?
• Timer malfunctioning?

Pool Equipment

• Auto-fill running?
• Leaking valves?

Other

• Outdoor shower
• Barn or outbuilding faucets
• Stock tanks
• Anything connected to your water system

Check Equipment

Pressure Tank

• Waterlogged tank causes rapid cycling
• But can also lose water through failed bladder
• Push Schrader valve on top—water sprays = bad bladder
• Tank feels heavy when empty = waterlogged

Check Valve

If the check valve (in well or at pump) fails, water flows back down the well.

Signs of Bad Check Valve:

• Pump runs for no reason
• Takes a moment to get water when first turned on
• Pressure drops when pump is off (even with no use)

Testing:

1. Note pressure on gauge
2. Turn off power to pump
3. Watch gauge
4. If pressure drops steadily = check valve failing
5. (Rule out house leaks first)

Visible Pipes

• Check around pressure tank
• Connections to well head
• Any accessible plumbing
• Look for drips, wet spots, mineral deposits

Underground Leaks

Signs of Underground Leak

• Wet spot in yard that never dries
• Greener grass in one area
• Water bubbling up
• Sinking or soft ground
• Higher than normal pump run time

Finding Underground Leaks

• Listen along pipe route (with mechanical stethoscope)
• Professional leak detection (acoustic equipment)
• Thermal imaging in some cases
• Pressure test sections of pipe

Common Leak Locations

• Where pipes change direction
• At fittings/connections
• Where pipes cross other utilities
• Under driveways or structures

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 run when nobody is using water?

Leak somewhere in the system. Water leaving causes pressure drop, pump responds. Find and fix the leak.

How do I find where my well system is leaking?

Start with toilets (dye test), then faucets, outside faucets, irrigation. Check pressure tank and check valve. If not found, may be underground.

Can a bad pressure tank cause this?

Waterlogged tank causes rapid cycling. Failed bladder can technically leak water. But more often, the "leak" is elsewhere in the system.

What if I can't find the leak?

May be underground or in well (check valve). Professional leak detection can pinpoint it. Don't ignore—pump is being overworked.

How much water could a running toilet waste?

Up to 200 gallons per day or more. This causes significant pump cycling and wastes water. Always check toilets first.