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How to Replace a Toilet Flapper

Although home plumbing repair projects may seem intimidating, there are many quick, easy tasks that you can do yourself. In this article, I’ll explain how to replace a toilet flapper, which is a simple, affordable fix to the common problem of water continuously running in the toilet tank.

A flapper valve covers the opening where water is drained from the toilet tank into the bowl. When the flapper valve is old and worn, the seal becomes compromised and water drains from the tank, causing the toilet to cycle over and over. This cycling is the repetition of water draining out of the tank through the compromised seal into the bowl. The float in the tank then goes below the fill level, triggering the ball cock valve to open and restore the water in the tank to the fill level. This wastes water and leads to a costly water bill.

The simplest solution is to purchase a new toilet flapper and install it yourself. The flapper can be purchased on its own or as an assembly with the flapper, float and chain. It is also available as part of a complete rebuild kit for one-piece toilets if you are in need of additional parts.

  1. First, shut off the water supply to the toilet tank. The knob is located on the wall near the toilet. Turn it to the right to shut off the water.
  2. Next, flush the toilet. This will empty the water from the tank.
  3. Remove the lid from the tank and locate the chain hooked to the flush lever. Unhook the chain from the lever.
  4. Remove the flapper by pulling at both sides to remove it from the pegs on the overflow tube. You can discard the old flapper.
  5. Attach the new flapper by placing the holes on either side over the pegs on the sides of the overflow tube.
  6. Connect the chain on the flapper to the flush lever.
  7. Ensure the flapper closes properly and forms a tight seal.
  8. Turn on the water supply to the tank.
  9. Once the tank is filled, flush the toilet.
  10. After the tank drains, the flapper should drop down and form a seal, allowing the tank to fill with water. Adjust the chain length and the flapper float level, if necessary, to allow the flapper to drop down and close. It should now be blocking the flow of water from the tank.
  11. You can test the seal for leaks by adding food coloring to the water in the tank. If you see the coloring appear in the bowl, then you know there is a leak. Try draining the tank and wiping off the rim of the drain opening to remove any debris that may be preventing a good seal.

As you can see, by following a few simple guidelines, you can learn how to fix a toilet on your own, saving yourself money in the process. Be sure to check out other home plumbing repair articles from CompletePlumbingSource.com, as well as our helpful glossary of plumbing tools and supplies to help you better understand the terms in this article.


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