How to fix toilet fill valve

If you have an older toilet, a faulty fill valve can cause it to leak, wasting water and money. Generally, your best bet is to replace it. It won’t take you much time, and the replacement part isn’t expensive.

Índice Show

Check the Fill Valve for a Leak
Remove and Replace Old Toilet Fill Valve
Install the New Fill Valve
Connect the Fill Tube

In the next few minutes, I’ll show you how to put a new fill valve on your toilet. If your toilet is having other problems, watch our video “Diagnosing a Leaky Toilet” to figure out which component inside the tank might be leaking.

The fill valve lets water into the tank and a float keeps the water in the tank from getting too high. The valve assembly includes the float and a shut-off mechanism to stop the flow of water.

Before you visit your local independent home improvement retailer to pick up your new fill valve, here’s something you should know. The best fill valves offer anti-siphon protection. In fact, your local building codes may require this type of valve. Anti-siphon protection prevents toilet tank water from getting siphoned back into your home’s water supply. Regardless of your building codes, installing an anti-siphon valve is a good idea.

Start by turning off the water supply to the toilet.

Remove the lid to the tank. Inside the toilet, you’ll want to remove the refill tube attached to the overflow pipe on the flush valve.

Flush the toilet by holding down the tank lever to get as much water as possible out of the tank. You can use a sponge or a towel to get the rest of the water out.

Next, disconnect the water supply line from the tank. You may need to use an adjustable wrench or a pair of channel locking pliers to loosen the connection.

Then remove the old fill valve by removing the lock nut beneath the tank.

The new fill valve goes on the way the old one came off.
Place the shank washer over the threads of the shank on the new valve, flat side up. Then insert the fill valve into the hole in the bottom of the tank.

While holding it in place, use a tape measure to see if the valve is set at the proper height in relation to the overflow pipe. If you need to adjust the height of the valve, press up on the lock ring to disengage it and turn the shank to adjust the fill valve to the proper height. Once it’s set to the correct height, pull the lock ring back down to lock the shank in place.

Don’t forget to attach the refill tube to the top of the overflow pipe.

Finally, reattach the water supply connection beneath the tank and turn on the water. Finally flush the toilet to make sure that if it fills back up properly, and check for any leaks beneath the toilet. If the valve is leaking under the tank, tighten the connections.

If you have questions about this or any other home improvement project, be sure to read our list of Frequently Asked Questions for this video. And be sure to print out our Project Instructions, which includes a Tools and Materials checklist, before visiting your local independent home improvement retailer. That’s where you’ll find all the products and helpful advice to complete your project. If you’re not sure where to find your local store, check out our Store Locator.

Good luck with your project and thanks for watching.

Home House & Components Fixtures Toilets

Time

Complexity

Cost

Fixing a running toilet is a lot easier than you might think. In this article, we'll show you how to identify and solve the problem. Don't be intimidated by the plumbing. The fixes are straightforward, even if you don't have any plumbing experience. So stop wasting water and fix the toilet!

Push down on the flapper with a stick when you hear the water running and listen for it to stop.
If it stops, you know the flapper isn't sealing properly. Replace it.
Check the fill tube length and cut it back so it's at least 1/2-in. above the water line.
To replace the flapper, first shut off the water supply valve under the toilet (or the main supply if the valve leaks!).
Flush the toilet to drain out most of the water, then unhook the old flapper.
Buy a new flapper of the same type and install it according to the instructions on the package.
Hook the flapper chain onto the flush lever arm so there’s a little slack when the flapper is closed.

The Family Handyman

Check the Fill Valve for a Leak

Flush the toilet and look for a fill valve leak.
Lift up on the toilet float arm when the tank is filling to see if the water stops.
Bend or adjust the toilet float arm so the tank stops filling when the water level is 1/2- to one-inch below the top of the overflow pipe.
If the fill valve still leaks, replace it as shown in the next photo.

Remove and Replace Old Toilet Fill Valve

Turn off the water supply, flush the toilet and sponge the remaining water from the tank.
Disconnect the water supply line, unscrew the fill valve locknut and lift out the old fill valve.

Install the New Fill Valve

Insert the new fill valve into the tank according to the instruction sheet and tighten the locknut a half turn past hand tight.
If the fill valve is at its maximum height, but the overflow pipe is still higher than the critical level mark, shorten the overflow pipe with a hacksaw so it's one inch lower than the critical level mark on the fill valve.

Connect the Fill Tube

Attach one end of the new fill tube to the fill valve nipple and the other to the enclosed angle adapter (shorten the tube to avoid kinks, if necessary).
Clip the angle adapter onto the overflow pipe.
Finish the installation by attaching the flapper chain to the flush lever as described above.
Turn on the water and test-flush the toilet.

Originally Published: November 25, 2019

Download Article Download Article

A faulty toilet fill valve can cause your toilet to run all the time or otherwise malfunction. However, the good news is that replacing your toilet fill valve is something any homeowner can do. It does not take a lot of experience with plumbing or a lot of time. However, you do need a few parts, a couple of tools, and a little bit of effort.

1
Turn off the water supply. Before doing any repairs to your toilet you should turn off the water outside of the toilet. You should have a water valve directly below the toilet tank. It should be located between where the water pipe comes out of the wall and where it attaches to the bottom of the toilet tank.[1] X Research source Go to source
- In most cases, you will turn the water shutoff valve clockwise to turn it off. Be sure to continue turning it until it stops moving.
EXPERT TIP

James Schuelke
Professional Plumber
James Schuelke, along with his twin brother David, is the co-owner of the Twin Home Experts, a licensed plumbing, leak detection, and mold inspection company based in Los Angeles, California. James has over 32 years of home service and business plumbing experience and has expanded the Twin Home Experts to Phoenix, Arizona and the Pacific Northwest.

James Schuelke
Professional Plumber

It's a good idea to turn off your main water valve, as well. Find the main water shut-off valve on the outside of your home and turn it off. Then, go around your property and turn on various fixtures to confirm that they're off, but it will also drain off residual water that's inside the system. Doing this will help you avoid water damage due to a flood.
2
Drain the toilet tank. Once the water is turned off, drain the tank before you can disconnect the toilet fill valve. To begin draining the tank, flush the toilet and hold the flush lever down to remove as much water as possible. Once most of the water is gone, you will need to use a turkey baster or a wet-dry vacuum to get rid of the small amount of water sitting at the bottom of the tank.[2] X Research source Go to source
- If you don't have a turkey baster or wet-dry vacuum, use an old towel or sponge to soak up the remaining water and any sediment left in the tank.
3
Locate the toilet fill valve. Remove the tank lid carefully and set it on a towel out of the way so it doesn’t get broken. The toilet fill valve is located inside the toilet tank, usually off to one side. In newer toilets, it is the entire plastic column that includes the float and the on-off lever for filling. In older toilets, the float is a separate piece but it will be connected to the top of the fill valve. [3] X Research source Go to source
- The fill valve also has a tube attached to it that connects to the overflow pipe.[4] X Research source Go to source
4
Detach the toilet fill valve. Loosen the nut that secures the fill valve to the water supply line by turning it counterclockwise with pliers or a wrench. Then, carefully pull the supply line out of the valve underneath the tank.[5] X Research source Go to source
- As you unscrew the nut, a bit of water may drip out of the tank. Keep a towel on hand or on the floor below the opening to catch any water that comes out.

1
Purchase a new toilet fill valve. Go to your local hardware store and purchase a new toilet fill valve. Most new toilet fill valves are universal, meaning they will fit in almost any toilet. However, if you are worried about fit, take your old toilet valve with you to the store and use it to assess whether a potential replacement will work.[6] X Research source Go to source
- Even if your old toilet fill valve had a separate float, a newer valve with the float integrated onto the shaft will work.
2
Put the new toilet fill valve in place. Remove the new toilet fill valve from its packaging. Be sure to read the directions it comes with. The fill valve should come fully assembled, so you should be able to put it straight into the toilet.[7] X Research source Go to source
- Remember to also clip the new refill tube to the overflow tube.
3
Make sure all the washers are in place. It is important to pay attention to how any included washers and nuts should be attached to the valve. There should be washers on the inside and the outside of the tank where the fill valve goes through it.[8] X Research source Go to source
- Washers on the inside and outside of the tank ensure that there is a water-tight seal around this connection point.
4
Tighten the fill valve nut carefully. When you have the toilet fill valve in place, the final part of its installation is to tighten a lock nut onto the threaded part of the valve. This is located on the underside of the tank. When doing this, it is important not to tighten the nut too hard. The nut should be tightened by hand to ensure that you don't tighten it too much.[9] X Research source Go to source
- Tightening the nut on the bottom of the fill valve with a wrench or pliers could crack the toilet tank or the valve.
5
Reattach the water supply line and turn on the water. Once the replacement fill valve is in place, it's time to get the water flowing again. Attach the supply line to the bottom of the new fill valve. Make sure that there is a washer inside the end of the supply line and tighten it with a wrench until it’s tight. Then turn on the water by turning the shutoff valve counter clockwise until it stops rotating.[10] X Research source Go to source
- Be careful not to overtighten the washer, or the nut could crack and the connection will leak.
- If you see any leaks, immediately turn the water off at the shutoff valve.
- When you turn the water on, the tank should start filling right away.
EXPERT TIP

James Schuelke
Professional Plumber
James Schuelke, along with his twin brother David, is the co-owner of the Twin Home Experts, a licensed plumbing, leak detection, and mold inspection company based in Los Angeles, California. James has over 32 years of home service and business plumbing experience and has expanded the Twin Home Experts to Phoenix, Arizona and the Pacific Northwest.

James Schuelke
Professional Plumber

Be very cautious as you turn the water back on. Once the valve is on, turn the main water supply on very slowly, and have a second person go into the bathroom and make sure there are no leaks as you regenerate the water system.
6
Adjust the float. Once the water is turned back on and your toilet tank has filled, then you can adjust the float on your new toilet fill valve. The float's location can be adjusted with a clip on its side, a set screw at the top of the float shaft, or by adjusting a screw at the top of fill valve where the float attaches.[11] X Research source Go to source
- Look at the directions of your new toilet fill valve for exact directions for float adjustment.
- When positioned correctly, the top of the float should be set at about 1 inch (2.5 cm) below the top of the overflow pipe. The goal is that the float comes up and shuts off the water before the water gets high enough to flow over the top of the overflow pipe.

A wrench or pliers
New toilet fill valve kit
Bucket
Towel

This article was co-authored by James Schuelke. James Schuelke, along with his twin brother David, is the co-owner of the Twin Home Experts, a licensed plumbing, leak detection, and mold inspection company based in Los Angeles, California. James has over 32 years of home service and business plumbing experience and has expanded the Twin Home Experts to Phoenix, Arizona and the Pacific Northwest. This article has been viewed 171,983 times.

Co-authors: 8

Updated: July 21, 2022

Article Rating: 90% - 68 votes

Categories: Featured Articles | Toilet Maintenance

Print
Send fan mail to authors

Thanks to all authors for creating a page that has been read 171,983 times.

"This article really aided my comfort/confidence level in going forward with my project! I am a mature and intelligent homeowner who has made this repair in the past, but it's been 20 - 30 years, so a quick tutorial was very valuable."

"Article pretty much gives a blow-by-blow account of how to replace toilet fill valve. Also give a list of things you will need to complete the task and a list of things to watch for so you don't run into issues."
"A good checklist. I don't repair/replace these valves very often. It's good to have a reference with drawings."
"My husband and I now feel we can fix anything!"