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What is the most common cause of a running toilet leak?

A worn or warped toilet flapper is the most common cause of a running toilet. A faulty or misadjusted fill valve is the next likely issue. In many Las Vegas homes, our techs start with a dye test and a flapper inspection, then check the fill valve and anti-siphon parts. We offer a Free Toilet Repair Diagnostic and can provide same-day service if booked by 6 PM. Our trucks carry common parts for on-the-spot fixes.

Quick checks:

  • Do a dye test in the tank.
  • Inspect the flapper for wear or gaps.
  • Ensure the fill valve shuts off at the right water level.

Updated: 2025-12-24

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