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Carney All Seasons Blog

What Causes a Toilet to Run?

A constantly running toilet is one of the most frequent plumbing problems we encounter in our work. People often ask us what causes a toilet to run and what they can do about it. There isn’t one simple answer to this question; a number of issues can occur in the tank of your toilet that will make it continually run water after it has last been used.

There are two things about a running toilet that you should know upfront: First, don’t panic—a running toilet is rarely a cause for flooding in your home. Second, you need to get it taken care of as soon as possible because of the enormous waste of water it causes. A running toilet can use 2 gallons of water a minute, so imagine the amount of water that will go to waste if it stays running for a few hours.

A plumber will then go down a list of the reasons for that nonstop running. The plumber will lift off the lid from the tank (very carefully, because lids are expensive to replace should they break) and point out the various places where the trouble might lie:

  • The flapper: This seal on the bottom of the tank can become loose from age deterioration. Since it’s supposed to stop water from flowing out of the tank, it will need to be replaced to create a watertight seal.
  • The chain: The chain to the flapper can be tangled or too tight, in which case the flapper won’t be able to close.
  • The ballcock: This valve device, usually near the handle on the tank, controls the flow of water. When the float (see below) rises high enough, the ballcock will shut off the flow. A malfunctioning ballcock won’t prevent the water from continuing to run.
  • The float: This balloon-like object rests on the top of the water, and when it rises high enough, it will cause the ballcock to close off the flow. If the float breaks, it can’t measure the water level.

Hopefully, this advice will help you get to the bottom of what’s happened. If you find yourself confused or worried about your running toilet, don’t hesitate to contact a Carney Plumbing Heating & Cooling professional. Our plumbers can fix most running toilet problems in a short time, so you won’t have money going down the drain.

We’re available with same-day service when you need plumbing assistance. Feel free to ask one of Carney Plumbing Heating & Cooling’s plumbers in Blue Bell, PA anything: we wouldn’t offer a 100% satisfaction guarantee if we weren’t confident in our answers!

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