What's actually causing this
Toilets run when water continuously trickles from the tank into the bowl. The two most common culprits are a worn-out flapper that doesn't seal properly, and a fill valve that's stuck open or set too high.
What you'll need
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Step-by-step fix
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1
Diagnose the problem
Lift the tank lid and add a few drops of food coloring. If color appears in the bowl within 10 minutes without flushing, the flapper is leaking.
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2
Turn off the water supply
Turn the shutoff valve behind the toilet clockwise. Flush once to empty the tank.
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3
Replace the flapper
Unhook the old flapper from the overflow tube pegs. Snap the new flapper in place and reconnect the chain — leave about half an inch of slack.
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4
Adjust the fill valve
If water is running over the overflow tube, the water level is too high. Adjust the float arm or float ball downward until the water sits 1 inch below the top of the overflow tube.
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5
Turn water back on and test
Slowly open the shutoff valve. Let the tank fill and listen for any continued running after the fill cycle completes.
In Austin, tap water is hard (240–320 ppm). Austin's water is hard, sourced from limestone aquifers. Scale buildup is visible within months. Water heater sediment accumulation is rapid. Water softeners are increasingly common among informed homeowners.
Plumbers in Austin typically charge $95–150/hr. Most homeowners budget $800–2,500 for common repairs like fixture replacement, drain clearing, or valve repairs.
Texas minimal licensing. Austin requires permits. Homeowners can obtain permits and perform plumbing work.
Post-1970s suburban construction dominant. Copper and PEX standard. Hard water means water heaters fail faster (8–10 years). Sediment buildup is common. Limestone subsoil can cause cracking and foundation settling. Slab-on-grade is common.
Freeze risk in Austin is minimal — hard freezes are rare. Pipe insulation is generally not a concern, though occasional cold snaps can surprise under-prepared homes.
DIY in Austin: Austin is very DIY-friendly. Texas's permissive licensing, affordable permits, and tech-savvy population support homeowner repairs. Hard water management is a common DIY focus. HVAC maintenance is often DIY-handled.
- The tank or bowl has visible cracks.
- The toilet rocks or is loose at the base — this may indicate a wax ring failure.
- Water appears on the floor around the base after flushing.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Austin.
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