3 Reasons Water Keeps Running In Your Toilet

In today’s day and age, with the ever-rising utility costs and the increasingly efficient toilet flushes, we do not want to see our toilets running constantly.

It means that you must have a problem, and it will be raising your water bill slowly but surely. Which also prompts you to call for necessary plumbing services. There may come a time when your old toilet is just not efficient anymore and you need to upgrade. Here you can read more about how long a toilet should last.

Keep reading to learn the answer to the question, “why does the water in my toilet keep running?”, and how you can fix it if you choose to not replace it.

What are the components in my toilet?

Before answering the question, “why does the water keep running in my toilet?”, we’ll go over the various components of a modern toilet.

Tank: Let’s start with the tank. The tank is the back of the toilet that holds the water. 

Fill Valve: Inside your toilet tank will be the fill valve. This is what the water line connects to on the underside of your toilet’s tank. This is what will fill the toilet tank with water.

Float: The float is attached to the fill valve and will tell the valve to turn on and off. Older toilets will have a ball on a metal rod as afloat, while most newer toilets will have a sliding plastic container around the fill valve.

Flapper: The flapper will be located at the bottom of the tank, and it will be what the flush handle is attached to, generally with a small chain. When you push down the handle, it will pick up the flapper, and the water will flush into the toilet.

Overflow tube: This will be the tube that the flapper is attached to that comes straight up and out of the water. The purpose of the overfill tube is that if the water level in the tank gets too high, it will go into the overflow box and the toilet bowl instead of onto the floor.

Fill tube: You will see a small tube from the fill valve go into the overflow tube. This small tube is so that the toilet can put water back into the toilet bowl once it has been flushed.

The fill tube

It is common for the fill tube to get hung up if it is too long. If the fill tube holds the float down or keeps the flapper from closing, then the water will slowly leak into the toilet bowl, which will give you the constant running effect.

Luckily this is a straightforward fix. Take the top of the tank off and inspect where the fill tube is running. If it is a problem, you should be able to see it relatively quickly. The fill tube is attached to the top of the fill valve and runs to the overflow tube.

Sometimes the fill tube will get twisted and keep the handle from setting back down how it should. If the handle cannot set back down, it will keep the flapper up, allowing the water to run.

Another way that the fill tube can lead to issues is if it gets twisted and keeps the float from fully coming to the top. If the float cannot rise to the top, the fill valve will continue to think that the toilet is not full and keep filling the toilet up. 

If the fill tube is holding down the float or holding up the flush handle, then the only thing you can do is trim the fill tube. Most often, if the fill tube is causing problems, it is too long and gets twisted around and in the way of other things. 

If the fill tube is not too long, it may be that it just ran in an inferior placement. You can usually unhook it easily and re-run it in a more strategic location.

Overflow tube

The overflow tube is designed to keep your toilet tank from overflowing onto the floor. This usually only becomes a problem when the float on the fill valve malfunctions and continues to fill the toilet with water. Once the water reaches a certain level, it will flow down the overflow tube into the toilet bowl and cause the toilet to continue to run.

To fix this, you will need to resolve why the toilet continues to fill. It may be cutting your fill hose shorter or running it more efficiently. Or there may be another problem.


Why does water keep running in toilet models? The flapper is a common cause.

The flapper is one of the most notorious issues for having a constantly running toilet. This can happen for many different reasons. One is if the flapper has gotten old and cannot make a good seal anymore. This is not very common because flappers will typically have a long life span.

The following reason is that the flapper has sustained damage for an unexpected reason. The most common will be the adjusting chain that connects the flapper to the flush handle, catches it, and tears the rubber. If the flapper gets a tear in the edge or cannot seal, it will allow the water to continue to run past it.

Lastly (and most commonly), a flapper can fail because the tail end of the chain connecting the flush handle is too long, and it gets stuck underneath the flapper. Similarly, when the slack in the chain keeps the flapper from going back down, this will usually allow much more water into the toilet bowl and will be a pronounced problem.

To fix a chain issue, you will need to either cut off the excess tail of the chain so that it cannot get under the flapper anymore. Or shorten the slack in the chain if it is the slack that is causing the issue and not the tail. Here is an excellent article regarding toilet repair.

Now you know the answer to the question, “why does the water in the toilet keep running?”.

What if my toilet runs all the time trying to fill back up?

If your toilet has to run for extremely long periods to try and fill back up, it could be something that has gotten stuck in your fill valve. This is common in older homes with metal plumbing pipes and rural homes after they have turned the water off to the house and turned it back on. 

Turning the water off and on tends to break up the sediment, rust, and anything else in the water lines, which settles in the screens of your faucets and your toilet valves. If your toilet fill valve is filling very slowly and doesn’t seem to be working right, this may have happened, and it will need to be replaced. 

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