Introduction

Toilets are a necessary part of any modern household. Contemporary plumbing keeps bathrooms sanitary and helps prevent the spread of bacteria and diseases by eliminating human waste before it has time to develop problems. They also make bathrooms and homes smell better. But toilets often come with their own problems, especially when the pieces break down or something goes wrong. One of the most irritating but less serious issues is when the water level in the toilet bowl is too high or too low, resulting in an expensive water bill or trouble flushing properly. To fix this problem, you need to know how to adjust the water level in a toilet.

Here’s the key idea. The water level in the bowl itself is mostly set by the toilet’s built-in trap, so what you actually adjust is the water level in the tank. The tank level controls how strong the flush is and whether water keeps running into the overflow tube. If the bowl water is low even with a full tank, check that the small refill tube is clipped to the overflow tube, look for a partial clog, or ask a plumber to check for a blocked vent or a cracked bowl.

Determining Toilet Type

Toilets are complicated to those who don’t understand them but surprisingly simple once you do. Most homes will have one of two types of fill valve – either one with a cylinder float or a ball and arm float. The float controls the water level in the tank.

To figure out which type of toilet you have, remove the porcelain lid from the tank on the back of the toilet. Inside will be a couple of different pieces. What you are looking for is either a ball-shaped object or a cylinder. They are recognizable on sight.

The ball typically sits on top of the water in the tank and will descend and ascend with the surface. Once it reaches a certain height, it shuts the fill valve, which stops water from entering the tank. The cylinder, on the other hand, slides up and down the fill valve shaft as the water level rises and falls, and shuts the valve off the same way.

Adjusting a Cylinder Float

Adjusting a cylinder float is easy. First, remove the porcelain tank lid and set it somewhere safe on a towel. Find the shutoff valve, which tends to be located behind the toilet near the pipe coming out of the wall or floor, in case you need it. Then, you need to find the adjustment stem. This is a long, slender rod or screw beside or on top of the cylinder float. It connects the float to the fill valve.

Once the adjustment stem is located, search for a release clip or an adjustment screw or dial. Either piece should be along the side of the stem or on top of the valve. The release clip can be pinched, allowing you to move the float up or down depending on your desired water level. A screw or dial will also control the float, but should not be adjusted drastically in a single motion. Instead, make small turns, flush, and let the tank refill to check the level before turning more.

Once you are satisfied with the water level, release the clip so it locks in place. The water should stop about 1/2 to 1 inch below the top of the overflow tube, or at the line marked inside the tank.

Adjusting a Ball and Arm Float

Ball and arm floats are a bit different yet still similar to cylinder floats. Again, you need to remove the porcelain lid. Then, look inside the tank. Many tanks have a line marked inside that tells you where the water should be. If the toilet runs or the flush is weak, it most likely means the tank is not properly filled to that line.

A common reason the water level is off in this style of toilet is damage to the ball and arm. Check the pieces and look for wear, tear, and cracks. A ball that has water inside it will sit too low and won’t shut the valve off properly. If you see any damage, it might be time to go to the hardware store and find some replacements.

If this doesn’t seem to be a problem, you can adjust the ball and arm float by turning the adjustment screw at the very top of the fill valve, where the arm attaches. Some older arms can instead be bent gently down to lower the level or up to raise it. Using a screwdriver, make small turns and let the tank refill after each one. Once the water in the tank reaches the desired height, leave the screw alone and return the lid. Your toilet should no longer have a problem.

Replacing the Fill Valve

If neither of these methods work, it’s time to replace the fill valve. You can find replacement pieces at most hardware stores. These should come with instructions that need to be adhered to exactly in order to ensure the toilet functions properly. Before doing any work, remember to shut off the water valve and flush the toilet to drain the tank, then sponge out what’s left. Then you can get to work.

You’re going to need to do more detailed tasks, so be sure you are up to date with some plumbing basics. The most difficult part for many is properly removing and then reattaching the supply line. Tighten plastic nuts by hand plus a little more, since overtightening can crack them. Clip the new refill tube to the overflow tube with its end above the water line. If you’re unsure about the instructions that come with the pieces, consider contacting a plumber for more professional assistance.

Conclusion

An inconsistent water level in your toilet bowl can be a bother and leave you wondering what you’re supposed to do. After all, you can’t just stop going to the bathroom, as much as many wish to. If you can’t seem to get your water to stay consistent, check the fill valve. This piece refills the tank after a flush, and its refill tube tops up the bowl. You’ll need to identify the type of valve and remember to turn the water off before replacing it, but it’s an easy fix that most people can handle. For the full set of steps, Family Handyman’s guide to fixing a running toilet covers float and fill valve adjustments.

What’s Next

Now that you know how to adjust the water level in a toilet bowl, you can move on to more projects around the home. If you would like more guides like this one, or beneficial tips and tricks on how to fix your throne, learn more from this page. We update regularly with interesting content that can turn you into a regular handyman or woman.

Sources

• How to Fix a Running Toilet, Family Handyman
• Toilet Won't Flush? Here's Why and How to Fix It, Family Handyman