Listen first, then look inside
The sound tells you a lot. A hiss means the fill valve is still letting water in. A trickle every few minutes, with the tank refilling by itself, usually means water is leaking past the flapper into the bowl. A steady stream down the overflow tube means the water level is too high.
| What you hear or see | Likely cause | First fix |
|---|---|---|
| Tank refills every few minutes, no one flushed | Flapper not sealing | Clean the seat, adjust the chain, replace the flapper |
| Constant hissing while the tank is full | Fill valve failing or dirty | Clean the valve or replace it |
| Water pours down the overflow tube | Float or fill height set too high | Lower the float so water stops below the tube rim |
| Handle must be held down to stop the water | Chain too long or too tight | Adjust slack to about a finger's width |
| Water on the floor around the base | Supply line, tank bolts or wax ring | Stop and call, since these may not be a simple fix |
Rule out the supply line and base before you assume it is just a flapper.
Run the dye test
Put a few drops of food coloring in the tank and do not flush. Wait fifteen to twenty minutes. If color shows up in the bowl, the flapper or its seat is leaking. The test is simple and shows what a visual check can miss.
A flapper is a rubber piece that softens, warps or gets coated with minerals. Wiping the seat with a cloth sometimes restores the seal, but a flapper that is years old is cheaper to replace than to nurse.
Step-by-step repair
- Close the shutoff valve at the wall behind the toilet by turning it clockwise, then flush to empty the tank.
- Unhook the old flapper from its ears and the chain from the handle arm, and take it with you to match the style.
- Wipe the seat around the drain opening with a damp cloth to remove slime and grit.
- Attach the new flapper and set the chain with a little slack, so it does not hold the flapper up.
- Open the shutoff slowly and let the tank fill, then check the water level against the mark or the overflow tube.
- Flush a few times and rerun the dye test to confirm the leak has stopped.
If the fill valve is the problem
Fill valves wear out from sediment and age. Replacing one means disconnecting the supply line and nut under the tank, then installing a new valve. If the nut will not move or the line is brittle, stop. That is where a quick repair turns into a leak.
Call a plumber if
- The shutoff valve will not close or drips when turned
- Water leaks at the base or from the tank bolts
- The toilet runs after a new flapper and fill valve
- The bowl rocks or the floor feels soft
- You see damp ceiling spots below a bathroom
If a leak is spreading, close the main valve and call our 24/7 line. Keep people away from wet outlets until the floor is dry.
Running toilets in Woodridge homes
Woodridge's water comes from Lake Michigan through the DuPage Water Commission, and the Village's annual water quality report does not list a hardness figure. If you see mineral crust on the flapper or fill valve, test your tap and ask Public Works for the report before you decide the water is to blame.
Census-based estimates put the median Woodridge house at 1980, and about seven in ten are at least 35 years old. Toilets from that era often still have the original fill valve and a shutoff that has not been turned in decades. Replace that stiff shutoff valve when you do the repair, so the next one is easy.
A running toilet puts water into the Village's sanitary sewer as well as onto your bill. Fixing the leak early keeps that extra water out of the system. Swapping a flapper is maintenance, but ask Community Development at 630-719-4750 before replacing a toilet or moving its drain, since plumbing work is permit-required.
When the fix is more than a flapper
A cracked tank, a corroded fill valve seat or a toilet that has needed repeated repairs may be better off replaced. Our toilet repair team checks the parts, the base seal and the shutoff, then tells you whether repair or replacement is the better call. We state a clear price before work starts.
The same problem often shows up elsewhere in the house. A faucet that keeps dripping after you tighten it has a similar worn seal, and our faucet repair crew can look at both in one visit.
Rules in nearby towns follow a similar pattern. In Naperville, the city's permit guide lists plumbing work and replacing water or sewer service lines as permit work. In Darien, residents own the sewer from the curb to the home, so a persistent leak into the sewer line is their cost to fix.
Stop the running before the bill arrives
Call the 24/7 line if the repair does not hold. Dispatch can book a same-day visit when a technician is free.
Questions we hear
A leaking flapper lets water seep into the bowl, so the tank drops and refills. This is called ghost flushing, and the dye test confirms it.
More than most people expect. A leak you can hear can waste water all day, so fix it rather than ignore it.
Many fit, but flappers differ in size and shape. Match the old one at the store or take a photo of the flush valve.
Usually the chain is caught, the flapper is warped, or the seat is dirty. Adjust the chain, then clean and test.
Not usually. Close the shutoff valve behind the toilet and book a visit. Water on the floor or a valve that will not close is worth an immediate call.
The Village lists plumbing work as permit-required. A flapper swap is maintenance, but call Community Development to confirm your project.
A running toilet is usually a small repair, and a plumber can confirm that quickly.