Fix the Toilet Tank Not Filling: Why Is It Not Filling? What Could Be Causing It?

One of the most annoying things that can happen in a house is when the toilet tank doesn’t fill up. I have been there, and it’s not pleasant, to say the least! In this article, we’ll talk about what could be causing your water level at home to go down and how you can fix a toilet tank not filling.

The main causes of a toilet tank not working are:

1. Misadjusted Fill Valve
2. Low Water Pressure
3. Debris in the toilet tank
4. Damaged Trip Lever
5. Broken or misadjusted float arm or ball
6. Damaged overflow tube

How Does a Toilet Tank Work?

Toilet tanks are engineered to automatically fill up with water every time you flush. Normally, it can take about ten seconds for a toilet tank to fill completely. And the water level must be just below the overflow tube.

A toilet tank is incorporated with a number of moving components that make it work, and if even a single one fails, this could make your toilet tank not fill.

Every time you flush, a handle arm pulls up a chain linked to the flush valve and flapper inside the toilet tank. As a result, all water stored in the toilet tank is dumped into the toilet bowl. 

After the tank is entirely emptied, the flapper will once again cover the drain hole, and water begins coming into the toilet tank to refill it. A mechanism known as a float ball is responsible for determining when the toilet tank is refilled.

What Causes a Toilet Tank Not to Fill Up?

Because a toilet tank comes with a number of different moving parts, the chances of one of them malfunctioning are pretty high. If you’re experiencing problems with your toilet tank, first, you must identify what causes them.

Below, you’ll find some of the most common causes for your toilet tank not filling up.

While some of these reasons are not complicated and can be solved with relative ease, others might need you to seek professional help.

Before you begin analyzing the possible cause, be sure you familiarize yourself with your toilet tank’s different components. 

1. Misadjusted Fill Valve

A fill valve is an assembly of tubes that control when a toilet tank fills or stops filling. Depending on the type and age of your toilet tank, the fill valve might look significantly different. 

But the thing is, if it’s not properly adjusted, the fill valve might cause your tank to not fill correctly. Look at the fill valve and inspect if there are any obstructions or debris within the tube itself.

You must also inspect if the fill valve is correctly installed and without any noticeable cracks. You shouldn’t spot any water leakage. And if there is, you’ll need to replace it with a new one. Now, if the fill valve is intact, the problem might occur because it’s too tight and doesn’t allow the tank to fill properly.

Furthermore, you should inspect if your fill valve has a screw on its top because this controls the volume of water that enters. Turning the screw clockwise, you’ll let more water come in when the tank is filling. Sometimes, instead of a screw, you’ll find a clip on the side of the fill valve. Control the volume of water by simply sliding it up for more volume and down if you want less volume.

2. Low Water Pressure

If your toilet tank looks like it’s not filling at all even though there’s a flow of water, you might have an issue with water pressure.

Surely, low pressure can be a big problem not only for your toilet, but for your sink, shower, and other appliances as well.

Low water pressure is normally the result of a faulty water pump. Additionally, if you are living on the top floors of a tall establishment, you might be experiencing problems with water pressure as well.

Sadly, you can’t just fix this low water pressure issue by yourself. The best fix for this problem is to install a booster pump. But this is a task that should be done by an experienced plumber.

3. Debris In the Toilet Tank

If your toilet has been serving you for a long time, it is most likely that its tank has been filled up with obstructions and debris that could be consuming some space in the cistern. Children may also throw things into the toilet tank if they see it open.

4. Damaged Trip Lever

Another typical cause of your toilet tank not filling is a damaged trip lever assembly. In most such cases, the component that links to the handle has disconnected because of corrosion or some other similar damage.

You can determine the issue by taking out the cover of your toilet tank and checking the trip lever assembly. The issue can be quickly solved by buying a new part and replacing it.

It’s always a smart idea to take a picture of the problem and show it to the personnel of your local hardware shop. They will normally know exactly what you need to solve the problem.

If you don’t feel comfortable doing the replacement by yourself, the safest way is to get help from a professional plumber. An experienced plumber will have the tools and parts required to properly replace your faulty trip lever.

5. Broken or Misadjusted Float Arm or Ball

In most toilet tanks, the fill valve is controlled by a float arm and ball system. If these parts are worn out or damaged, it will most likely result in your toilet tank not filling. Even though the setup of the float arm and ball system is pretty simple, there are a number of ways in which problems can happen. 

In addition, you can fix almost all related issues yourself because there are float arm and ball kits in most local hardware stores.

In some cases, the float arm is misadjusted and doesn’t let water to come into the toilet tank. You can quickly fix this by just bending the arm upward. This will raise the ball to a new level. Some float arm and ball systems come with screws that should adjust in order to set the right height. You can try different positions until you find the one that works best.

If either the ball or arm is damaged or worn out, you simply have to replace them. As we’ve mentioned above, you can buy replacement parts at your local hardware store.

The float arm and ball systems are usually easy to install. But if you’re not confident in your abilities, again, it’s best to seek the help of a professional plumber.

6. Damaged Overflow Tube

An overflow tube is a large tube that transports surplus water in your toilet tank to the toilet bowl to prevent overflowing. This component is located right in the center of the toilet tank and is basically a part of the flush valve.

If your overflow tube is faulty, it will result in your toilet tank not filling while water is gushing into the toilet continuously. If this is the problem, the only choice you have is to replace the overflow tube with a new one.

The good part is that you can fix this issue by yourself with relative ease. Simply take out the overflow tube and put the replacement in its place. Obviously, you should ensure that the new tube is the same exact size as the previous one. On the other hand, you can simply replace the entire flush valve mechanism.

How to Fix a Toilet Tank Not Filling with Water

If you see that your toilet tank is not filling with water, what you want to do first is to narrow down the root cause of the problem.

Maybe the toilet fill valve is damaged, or perhaps there could be a problem with the water pressure. 

Sometimes, the problem could be a bit more complex such as a faulty toilet bowl that requires to be replaced or a problem within your sewer line.

Regardless of the cause, it is best to address the issue as soon as possible to prevent potentially bigger trouble with your plumbing.

Adjust the Float Ball

Most toilets are incorporated with a toilet float ball or also called ball float. This component works to control water inside the toilet tank. It is connected to a 10-inch to a 12-inch metal rod that is attached to the toilet tank’s fill valve.

Remember: Some latest toilet models may not have this traditional toilet ball.

Eventually, the float ball’s arm can become worn out or drop from its original position, which may cause the toilet to prevent it from filling properly or to leak. You can adjust the float ball manually if it has fallen from its position.

What you want to do is first remove the toilet lid. Then grab the float arm and bend it upwards around ⅛ of an inch. If your float arm is incorporated with a screw attachment, you can also adjust this part as well.

After that, flush your toilet to see if the tank fills properly. If it is still low, just adjust the float arm until the water fills to the correct level.

Adjust the Fill Valve

The fill valve or also called a flush valve is also usually one of the main causes of a toilet tank not filling properly. This component is a tube assembly found inside the toilet tank. Its primary job is to refill the tank after the toilet is flushed.

Depending on the brand, the actual setup of the fill valve may differ, but you should still be able to easily adjust it if needed.

If your flush valve has a screw on its top, you can normally adjust it with a flat head screwdriver. To do this, simply turn the valve clockwise to let in more water inside the toilet tank. Just turn the flush valve counterclockwise if needed. Then, flush the toilet to see the new water level and keep adjusting as necessary.

Meanwhile, if your fill valve has a screw that has a clip on the side, use your thumb and index finger to slide it up to increase the water level. Just move it down if you want to decrease the water level. You may have to play with it a bit to achieve the level you want.

Replace the Trip Assembly

A trip assembly is an L-shaped plastic or metal lever that is linked to the toilet handle. 

In some cases, the trip assembly inside the toilet can malfunction, and this causes the toilet tank to fill up with less water than it should.

When you push the toilet flush handle, the lever lifts to open up the slapper inside the toilet tank, and this lets the water to drain out and freshwater to enter the toilet bowl.

Depending on the toilet model and brand, the lever may also come linked with its own housing.

In regards to this, if the lever breaks or becomes faulty, you must replace it with a new one. And if it is linked to an assembly, you will also have to buy the complete repair kit. Still, it is a cheap and easy fix.

Replace the Overflow Tube

The overflow tube inside your toilet’s tank can also be the cause of water level problems. For that reason, it will prevent water from filling up the toilet to the proper level. Sometimes, it can cause the toilet to fill up with excess water.

When dealing with the cause of your toilet’s water level problem, inspect the overflow tube to see if it’s damaged or worn in any way. If this is the case, you must replace the component.

To do so, begin by turning off the water supply line at the water valve. Then, take out the washer, the plastic outlet ring, as well as the screws that keep it in place.

Now, pull the tube out from its position. Install the new tube, and make sure to fasten the screws using a screwdriver. Then, turn the water supply back on, and flush the toilet to see if it’s all good. 

Check for a Blocked Sewer Vent Line

In some cases, clogs in the sewer vent line can cause low fill levels in your toilet tank. If you notice gurgling noises coming from the bowl or you smell any foul-odor gases emitting from the toilet, this is most likely the problem.

These blockages can be caused by several things, such as leaves and carcasses from local wildlife getting caught or non-biodegradable items being flushed down the toilet. If you’re certain that this is the cause, what you want to do is simply clear the vent line of the clog.

You can try to do this by yourself if you are familiar with your property’s sewer system. But it may be wiser to get in touch with an experienced professional plumber who can utilize professional tools to unclog the line quickly and safely.

What Happens If the Fill Valve Is Bad?

If the fill valve is bad, your toilet tank can start filling significantly slower than normal and eventually halt filling at all. When the toilet tank fills slowly, it may not fill completely between flushes, which can contribute to a weak flush and can ultimately lead to toilet drain blockages.

Can a Toilet Fill Valve Be Repaired?

A toilet fill valve can be repaired depending on the model of it used in your toilet tank. Some brands such as Fluidmaster enable for quick replacement by replacing the seal inside the component. Though, you should keep in mind that some brands may not be so repair-friendly. If the toilet fill valve can’t be repaired, obviously the only option left is to replace the entire component.

How Do I Get Water Back Into My Toilet Tank?

To get the water back in your toilet tank, first remove the toilet tank lid. The water level adjustment rod attaches the float cup to the fill valve. Rotate the screw on top of the water level adjustment rod clockwise. This will raise the float cup and improve the water level in your toilet tank.

Can You Manually Add Water to a Toilet Tank?

If for some reason, you don’t have running water in your home, you can still keep your toilet working by filling up the toilet tank manually.

You’ll need to get some buckets or any container to manually transfer water to the toilet tank. The obvious drawback of this is that you’ll need to fill the back of the tank for every flush, which is clearly a hassle.

Last update on 2022-10-30 / Affiliate links / Images from Amazon Product Advertising API