Fix a running toilet by finding which tank part lets water escape: adjust the chain, lower the float, replace the flapper or replace the fill valve. A worn flapper is the most common cause, and a new flapper costs only a few dollars at a hardware store.
A running toilet is a toilet that keeps sending water from the tank into the bowl after the tank is full. A leaky toilet wastes about 200 gallons of water per day, according to the EPA WaterSense program. A toilet that keeps running after these fixes needs our toilet repair plumbers in Marietta.
Why Does a Toilet Keep Running?
A toilet keeps running because water escapes past the flapper into the bowl, or spills over the top of the overflow tube, so the fill valve never shuts off. Five parts cause the problem.
| Cause | What happens |
|---|---|
| Worn or warped flapper | Water seeps from the tank into the bowl |
| Chain too short or tangled | Flapper cannot seal on the flush valve seat |
| Float set too high | Water spills into the overflow tube |
| Failing fill valve | Valve does not shut off at the right level |
| Cracked overflow tube | Water drains into the bowl through the crack |
How Do You Find Out Why Your Toilet Is Running?
Remove the tank lid and watch the water level. Water spilling into the overflow tube points to the float or fill valve. Water below the tube points to the flapper.
- Check the water level. Water stops about 1 inch below the top of the overflow tube, at the fill line marked on most tanks.
- Watch the overflow tube. Water flowing into the tube means the float sits too high or the fill valve fails.
- Run the dye test. Put a few drops of food coloring in the tank and wait 10 minutes without flushing. Color in the bowl means the flapper leaks, according to EPA WaterSense.
A silent flapper leak raises the water bill without any noise. Our guide to spotting leaks you cannot see covers the meter test for the rest of the home.
How Do You Fix a Running Toilet Step by Step?
Work through 5 fixes in order, simplest first: adjust the chain, lower the float, clean or replace the flapper, replace the fill valve, and replace a cracked overflow tube.
How Do You Adjust the Flapper Chain?
Adjust the chain so it has about half an inch of slack when the flapper is closed. A chain that is too tight holds the flapper open. A chain that is too long tangles under the flapper.
How Do You Lower the Float?
Lower the float so the water stops about 1 inch below the top of the overflow tube. Turn the adjustment screw on the fill valve, or slide the float cup down its rod. Older ball floats lower by gently bending the float arm.
How Do You Replace a Toilet Flapper?
Replace a toilet flapper by shutting off the water, flushing to empty the tank, unhooking the old flapper and clipping on a matching new one.
- Shut off the water. Turn the valve behind the toilet clockwise.
- Flush. Hold the handle down to empty the tank.
- Remove the old flapper. Unhook the ears from the overflow tube pegs and unclip the chain.
- Clean the valve seat. Wipe mineral buildup off the flush valve seat.
- Install the new flapper. Match the size (2-inch or 3-inch) and clip the chain with slight slack.
- Turn the water on and test. Run the dye test again.
How Do You Replace a Fill Valve?
Replace a fill valve by shutting off the water, draining the tank, disconnecting the supply line, removing the old valve and setting the new valve to the fill line. Fill valve kits include instructions for setting the height. Clip the refill tube to the overflow tube so it drips into the tube, not into the tank.
How Do You Fix a Cracked Overflow Tube?
Fix a cracked overflow tube by replacing the flush valve, which means removing the tank from the bowl. This repair takes more time and parts, and most homeowners hand it to a plumber.
What Tools and Parts Do You Need?
A running toilet repair needs a replacement flapper or fill valve kit, a sponge, a towel and, for a fill valve, an adjustable wrench.
| Item | Use |
|---|---|
| Replacement flapper (2-inch or 3-inch) | Stops seepage into the bowl |
| Fill valve kit | Replaces a valve that does not shut off |
| Adjustable wrench | Loosens the supply line and valve nut |
| Sponge and towel | Removes the last water from the tank |
| Food coloring | Confirms a flapper leak |
Take the old flapper to the store to match the size and style.
When Do You Call a Plumber for a Running Toilet?
Call a plumber when new parts do not stop the running, the overflow tube is cracked, or water leaks onto the floor.
- New parts do not stop the running
- The flush valve or overflow tube needs replacement
- Water leaks from the tank bolts or the base of the toilet
- The shutoff valve behind the toilet is stuck or leaking
A toilet that runs and clogs points to a drain problem; try our chemical-free drain unclogging methods first.
Related Toilet and Drain Guides
Frequently Asked Questions
Why does my toilet keep running?
Water escapes past a worn flapper or spills into the overflow tube because the float sits too high.
How much water does a running toilet waste?
A leaky toilet wastes about 200 gallons of water per day, according to EPA WaterSense.
How do I stop my toilet from running without a new part?
Adjust the flapper chain or lower the float. These 2 fixes need no new parts.
How long does a toilet flapper last?
A flapper wears out over the years as rubber hardens and warps, and hard water speeds the wear.
Can a running toilet raise my water bill?
Yes. A running toilet wastes water around the clock and raises the bill.
Toilet Still Running?
Tried the flapper and fill valve? Call (770) 230-0611. Plumber Marietta GA repairs and replaces toilets across Marietta.