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If you have a toilet that keeps running and the toilet flapper valve appears to be working properly, the problem is likely a toilet fill valve that needs adjustment. This problem is easy to fix if you follow the tips in this do-it-yourself video.

Tools & Materials Needed

  • Depending on the design for the fill valve in the toilet, a screwdriver may or may not be needed.

Steps To Adjust a Toilet Fill Valve

  1. Remove the lid from the toilet tank and set it on the floor.
  2. Some toilet tanks have a maximum water level mark printed or etched inside the tank, while others do not. There is a vertical tube called an overflow tube. The important part is that the water lever should be slightly below the top of this tube when the tank is full. If the water level is too high, it will be constantly emptying into this tube.
  3. The fill valve contains an adjustable float mechanism that shuts off the water when it reaches the maximum level. There are many designs for different types of fill valves and floats, but each has a method for adjusting the maximum water level. A quick inspection of the valve should indicate the proper method to use to make the adjustment. The adjustment is usually not hard to figure out.
  4. Adjust the valve so that when the tank is filled, the water level is just below the top of the overflow tube.
  5. Flush the toilet and wait for the tank to fill. Just before the water level reaches the top of the overflow tube, the water should shut off. If it doesn’t, adjust the valve and test it again.
  6. If everything is working properly, replace the lid on the toilet tank.

Toilet fill valves do go bad and periodically need to be replaced. If the adjustment does not work, you may have to replace the fill valve assembly. If you do not feel comfortable doing this, call a professional plumber or handyman.

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