How To Fix Toto Toilet Fill Valve

A toilet is composed of many parts that all work together to do one thing: flush. Knowing what each and every component does helps a lot when problems arise. Although you can always call in a professional to solve the issue, sometimes you’ll find that the problems you encounter can be solved with your hands alone.

One of the parts that comprise a toilet is the fill valve. This is the part in charge for refilling the tank after you have flushed. Just like any other part in any other system, the fill valve is also prone to wear and tear. Sometimes, the fill valve can be out of adjustment because of normal wear on its components.

With that said, when you notice you fill valve leaking or if water continues to run even after you’ve flushed, then there might be something wrong with your fill valve. If you have a Toto Toilet fill valve, this article will guide you on how to fix it.

Toto Toilets

Toto Toilets have been available in the market since 1985. They have redefined the domestic gravity flush toilet design with their new systems on a regular basis.

What You’ll Need

When fixing your toilet, you need to have all the essentials in place. For the task of fixing a Toto Toilet fill valve, you will need the following:

  • small offset pliers
  • food coloring

Now it may be odd to see food coloring in the list of items needed but continue reading on to find out what it will be used for.

Fixing a Toto Toilet Fill Valve

Here’s your guide to fixing the fill valve of your Toto Toilet:

Take the cover off the tank of your toilet. Be careful as you do this because the last thing you want is a ruined tank cover. Set the tank cover aside in a safe place.

Pour a little bit of the food coloring into the tank. After doing that, leave your toilet alone for about 15 minutes. If you notice the food coloring in the bowl, try adjusting the flapper to tighten it. The reason for the leaking may just be the flapper being a bit loose.

If Tightening the Flapper Didn’t Work…

If tightening the flapper didn’t work, then the only way to solve the problem is to replace or readjust the fill valve. Here’s a guide on how to do that:

  • Remove the tank cover. Do this step if you’ve replaced the cover back after performing the instructions above. Keeping the tank open allows you to see just how everything in there is working. You get to see how the internal components move and as such, can see where the problem might be.
  • Flush the toilet. As mentioned earlier, doing this action allows you to see the internal components of your toilet in action. Observe closely what happens when you flush because this will be important as you go along trying to fix the fill valve.
  • Turn off the angle stop. The angle stop is what supplies water to the toilet. After doing so, flush the toilet again. Keep in mind that you did flush the toilet once but water will start filling up again unless you stop the flow.
  • Disconnect and remove the black supply tube that is feeding the top of the flush valve.
  • Remove the cover of the fill valve. Doing this allows you to check whether there is debris in the valve. Sometimes, the root of the problem could just be debris that needs to be removed. If you see visible debris, make sure to get all of them out.
  • Take the internal float off. Do this by depressing the float arms inward. And make sure to do this carefully that you don’t do any more damage to the toilet. The last thing you want is an additional problem to solve.
  • Hold the body of the fill valve with one hand then twist the cap (either black or blue in color) counterclockwise then remove it. When doing this, avoid twisting the fill valve body because when you do, it will unlock the fill valve height adjustment.
  • Clean the cap assembly under warm water. As you do this, make sure to check the diaphragm for a tight seal and also ensure there is freedom of movement.
  • Lift the center tube out from the fill valve then remove the strainer. See if there is any signs of debris. After doing so, rinse all the parts under warm water.
  • Start replacing back the parts. But keep in mind to do this in reverse order of the steps listed above. After doing that, test the toilet again to see if the problem persists.
  • Check again for leaks. To do this, use the food coloring again. Drop a small amount into the tank and leave it there for about 15 minutes. If you don’t see it leaking into the bowl, then the problem with your fill valve has been fixed.

Another test you can do after resolving the issue is to check the toilet’s operation as stated in the specifications by the manufacturer.

Other Fill Valve Issues and Their Solutions

The fill valve turns on or off without the toilet being flushed

The most likely cause of this is that there’s no proper slack in flapper chain. To solve this issue, adjust the flapper chain for proper slack.

Another reason this might be happening is that the flush valve flapper is dirty. Try inspecting the valve to see if it’s dirty and if so, clean it and see if the problem still persists.

The fill valve continues running

This problem is most likely caused by a dirty fill valve seal. Here’s what you should do to fix it:

  • Turn off water supply.
  • Open the fill valve cap.
  • Clean the valve seal.

Another cause for this problem might be with the flush valve flapper not being seated properly. To fix this: check, clean then adjust the flapper position.

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