Running toilet — wipe the flush valve seat under the flapper

The flapper seals against a round flush valve seat at the bottom of the tank. Grit or mineral film there can keep a running toilet trickling even with a new flapper.

Wipe the flush valve seat to stop a running toilet

1. Turn off the supply valve and flush to drain the tank.
2. Lift the flapper and feel the rim under it.
3. Wipe the rim with a soft scrub pad until it feels smooth.
4. Lower the flapper, turn the water back on, and listen for a quiet tank.

If the seat is cracked or chipped, it needs a repair kit or a plumber.

Not sure the seat is the problem? Run the dye test and the rest of the toilet flapper check first.

More help

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