How To Fix Running Toilet
One of the most common and annoying problems with your toilet is the simplest to fix yourself. It’s often referred to as a “running” toilet. If your toilet is “running” or continuously in refill mode, it is a very easy do it yourself project.
The first thing to do when fixing a running toilet is to check the refill tube that runs from the fill valve, usually on the left side of the tank, to the flush valve, which is in the center of the tank. The end of the refill tube should be above the water line. If not trim it down, or adjust the fill level on your fill valve. Most modern fill valves have various settings for how much of the tank should be filled after each flush.
Another cause of a running toilet is a loose or worn flapper. The flapper is the red or black rubber part in the center of the toilet covering the hole of the flush valve. You can tell if the flapper is causing the problem if the noise stops when you press down on the flapper. A flapper is easy to replace, but there are many different sizes and mounting methods, so be sure to bring the old flapper to your neighborhood Ace Hardware store so they can match it up with the correct new flapper.
If the flapper and the fill tube both look good and you still have a running toilet, the fill valve is probably worn out and should be replaced. It’s also an easy fix, just pick up a new Fluidmaster or Korky fill valve at Ace and be sure you turn off the water supply before loosening the old fill valve.