A toilet that keeps running, or refills by itself every so often, is easy to ignore. It shouldn't be. According to the U.S. EPA's WaterSense program, a running toilet can waste 200 gallons of water or more every day. That shows up on your water and sewer bill.
Step 1: Find out if your toilet is leaking
Some leaks are loud. Many are silent. The easiest check is the dye test the EPA recommends:
- Put a few drops of food coloring in the tank (the back part, not the bowl).
- Wait 10 to 15 minutes without flushing.
- Check the bowl. If color shows up in the bowl, water is leaking from the tank. Flush afterward so the color doesn't stain.
Step 2: The usual suspects
- A worn flapper. The rubber flapper at the bottom of the tank seals the water in. Over time it warps or hardens and lets water seep into the bowl. The EPA notes this is one of the most common causes.
- A chain that's too short or tangled. If the chain holds the flapper slightly open, water keeps running.
- The water level is set too high. If water spills into the overflow tube (the open pipe in the middle of the tank), the fill valve keeps refilling. The water line should sit below the top of that tube.
- A failing fill valve. If the tank hisses or refills on its own even with a good flapper, the fill valve may not be shutting off.
What you can safely try
Jiggling the handle, freeing a stuck chain or lowering the float a little are fine to try. Turn the water off at the shut-off valve behind the toilet before you reach into the tank.
When to call a plumber
- The shut-off valve behind the toilet is stuck or leaks when you turn it.
- Water is leaking at the base of the toilet or onto the floor.
- You've replaced the flapper and it still runs.
- More than one toilet is running, or your water bill jumped and you can't find why.
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- How much water does a running toilet waste?
- According to the EPA's WaterSense program, a running toilet can waste 200 gallons of water or more every day.
- How do I know if my toilet is leaking?
- Put a few drops of food coloring in the tank and wait 10 to 15 minutes without flushing. If color appears in the bowl, the toilet is leaking.
- What usually causes a toilet to keep running?
- The most common causes are a worn flapper, a chain that holds the flapper open, a water level set too high so water spills into the overflow tube, or a failing fill valve.
- When should I call a plumber for a running toilet?
- Call if the shut-off valve is stuck or leaking, water is on the floor, it still runs after you replace the flapper, or your water bill jumped and you can't find the cause.