Why Is My Toilet Running?
TechXpert verified by Rob Ilie
Usually an internal leak will keep your toilet running constantly. Internal leaks in your toilet are often caused by one of three things: an old or cracked toilet flapper, a malfunctioning chain, or too much water in the tank.
A Broken Flapper
The flapper on your toilet is what’s responsible for sealing the water in the tank. As your flapper ages, the seal can break and allow water to leak from the toilet tank into the bowl. Water leaking into your toilet bowl causes your toilet to run non-stop.
The easiest way to fix your flapper is to replace it. Not sure what part to buy or how to go about replacing the old one? A plumber can help do the job quickly and easily.
A Malfunctioning Chain
Every toilet has a chain that connects the flapper to the flush handle. When you flush, the handle pulls the chain up to open the flapper seal that lets water flow. If your chain is too long, it can get stuck underneath the flapper.
When the chain is stuck under the flapper, the flapper can’t seal your tank properly and water will continue to escape the tank, causing your toilet to run constantly.
If you notice your flapper is too long, simply shorten the chain by unhooking it and re-attaching it so that there is less slack between the handle and the flapper. Make sure not to shorten the chain too much, or you’ll have the same issue: If it’s too short, the flapper won’t be able to seal properly and your toilet will continue to run.
The Water Level Is Too High
Too much water in your tank can also make your toilet run non-stop, because when the float in your tank is too high, your toilet is prone to overfilling. Luckily, adjusting the water level is simple: Lower your float arm so the water sits at the recommended level.
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