How to Fix a Running Toilet
That annoying running toilet wastes water and money. Here's how to diagnose and fix the most common causes in under 20 minutes.
Video by
Anthony
How To Do This
AI-generated step-by-step guide
Could not generate summary. Please try again.
Why Your Toilet Won't Stop Running
A running toilet is usually caused by one of three things: a faulty flapper, a misadjusted fill valve, or an overflow tube that's too high. Let's walk through each.
Step 1: Check the Flapper
The flapper is the rubber seal at the bottom of the tank. Over time it cracks or warps. Press down on it gently — if the running stops, you need a new flapper (about $5 at any hardware store).
Step 2: Adjust the Fill Valve
The water level should sit about 1 inch below the top of the overflow tube. If it's too high, water constantly spills into the tube. Turn the adjustment screw on the fill valve to lower the water level.
Step 3: Check the Float
If the float is waterlogged or set too high, the fill valve never shuts off. Replace a waterlogged float or bend the float arm down slightly.
Tools You'll Need
- Adjustable wrench
- New flapper (if needed)
- Sponge and bucket for cleanup
Safety Tips
- Always turn off the water supply valve behind the toilet first.
- Don't overtighten plastic fittings — they crack easily.
This is a beginner-level repair that saves hundreds of gallons per week!