A toilet that keeps running is a common plumbing problem that is often caused by a leak. There are a few reasons why this might happen, including a worn-out flapper, a float ball that’s too low or being blocked, or a refill tube that’s too long.

Replacing the Flapper The flapper is responsible for controlling the flow of water from the tank to the bowl. If it’s worn out or broken, it won’t seal the tank properly, causing water to continue running into the bowl. Replacing a flapper is a quick and easy fix that can be done by a professional plumber. It typically costs between £5 to £10.

Sometimes the chain connecting the flapper to the flushing handle is too long and gets stuck under the flapper. This prevents it from closing and causes water to keep running. Adjusting the chain length can fix this issue.

Increasing the Height of the Float Ball The float ball is a plastic balloon attached to a float arm that controls the water level in the tank. If the float arm is positioned too low or the ball is blocked from rising up, the toilet will continue running. Lifting the float arm to increase the height of the float ball can solve this problem. If the float ball has a crack, it needs to be replaced.

Shortening the Refill Tube The refill tube sends water down the overflow tube to fill the toilet after a flush. If the tube is not positioned properly over the overflow tube, the toilet won’t stop running. This can be fixed by repositioning the refill tube or by snipping the end of the tube to the proper length.

In summary, a running toilet is a common plumbing issue that can be caused by a worn-out flapper, a float ball that’s too low, or a refill tube that’s too long. These problems can be easily fixed by a professional plumber.