Why Won't My Toilet Stop Running?

A toilet that is constantly running will waste a lot of water and lead to higher water bills. Fortunately, this common plumbing problem can be taken care of by the average homeowner.

Before you get started on this do-it-yourself project, it may be helpful to understand what components are inside of the toilet’s tank.

  • Float: Looks like a medium-sized plastic ball extending outward from an arm, or a thick plastic ring with a tube going through it.
  • Flapper: The plug at the bottom of the toilet tank with an attached chain. It resembles a rubber drain stopper you might use in a sink or bathtub.
  • Overflow tube: Empties water into the toilet bowl and prevents the tank from flooding.

How does a toilet work?

When you flush the toilet, the flushing lever pulls on the flapper’s chain. The flapper swings up and allows fresh water from the tank to empty into the toilet bowl.

When water drains out of the toilet tank, the float sinks to the bottom of the unit. When this happens, it activates the fill valve.

The fill valve allows fresh air into the tank, which raises the float again.

Problems which can lead to a running toilet

  1. Flapper needs to be replaced. If the flapper isn’t creating a tight seal between the tank and the rest of the toilet, water may seep out. This can cause the float to drop and trigger the fill valve to let in more fresh water. Simply replace the flapper if it’s old or damaged.
  2. Float needs to be adjusted. The float should never be above the overflow tube. If you see that it is, this will cause water to continuously run. This can be fixed with a simple adjustment of the float.
  3. Flapper chain is too tight and needs to be adjusted. When the toilet hasn’t been flushed, the flapper chain shouldn’t be so tight that it’s letting water seep through. Be sure that the flapper is in the proper position and ensure that the chain is not too tight.

If these suggestions don’t help with fixing your running toilet, it may be time to call in a professional plumber.