Trigger
As soon as noticed (wastes water)
Who does it
DIY
Est. time
20-30 min
Est. cost
$10-25
Difficulty
●○○○○
Step by step
Remove the tank lid and flush to observe the flapper and fill valve.
Check chain slack on the flapper - adjust so it has slight slack when closed.
If the flapper is worn/warped, replace it with a matching universal flapper.
If water still runs, the fill valve may need replacing.
Turn water back on and flush several times to confirm it stops running.
Video guide
How To Fix a Running Toilet - This Old House
Watch this guide
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