Having a toilet that won’t stop running can be quite annoying. Not only will you constantly hear the tank refilling, but your water bill will also be higher since a running toilet can waste a lot of water. Luckily, there are only a few issues that can cause a toilet to run constantly, so it may be something that you can diagnose and possibly fix on your own. With that in mind, here are the issues to look for if your toilet won’t stop running and how each one can be fixed.

Worn-Out Toilet Flapper

The toilet flapper is the large rubber gasket located at the bottom of the toilet tank. It is connected to the flush lever by a chain. When you press the handle to flush a toilet, the lever raises and the chain lifts the flapper so that water quickly empties out of the tank and flushes the bowl.

The fact that the flapper constantly sits in water means that the rubber can slowly degrade over time to the point where the flapper no longer has a watertight seal. When this happens, a small amount of water will constantly leak out into the bowl and the tank will need to refill fairly often. While a leaky flapper may not seem like a big deal, it can result in more than 200 gallons of water being wasted each day.

If your flapper is worn out, you will need to replace it in order to stop the toilet from constantly running. Visually inspecting the flapper for damage can help you determine if it’s leaking. However, the easiest way to know if your flapper is leaking is to use food coloring. All you need to do is put a couple of drops of food coloring in the toilet tank and lit it sit for around half an hour without using the toilet. If the coloring makes its way into the bowl, there is a good chance that your flapper needs to be replaced.

Flapper Chain Is Too Short

Before testing for a leaky flapper, it is always a good idea to check the flapper chain to make sure it isn’t preventing the flapper from sealing tightly. If the chain is even a tiny bit too short, the flapper won’t ever drop far enough back down to fully seal the tank. This issue is extremely easy to fix as all you need to do is detach the chain and then adjust it so that it is slightly longer. However, you need to make sure that the chain isn’t too long, or else the flapper won’t lift, and the toilet won’t flush.

Misaligned Float

The toilet float works in conjunction with the fill valve to ensure that the tank refills to a certain level after each flush so that there is enough water for the next flush. Newer toilets typically have a cylindrical plastic float that moves up and down on the plastic fill tube or valve. If you have a much older toilet, it may instead have a rubber ball float. In either case, flushing the toilet instantly lowers the float. As the tank refills, the water slowly raises the float back up. Once the float returns to its original position, the fill valve closes and the toilet stops refilling.

If the float is set too low, the water level in the tank will always be too low, resulting in a weak flush. If the float is set too high, the water level in the tank will rise above the top of the overflow tube. This results in water constantly draining out of the tank through the overflow tube. The toilet will then continually run as the float will never rise high enough to trigger the fill valve to close.

Your toilet should have a mark on the back of the inside of the tank that shows the proper fill level, and this is usually about one inch below the top of the overflow tube. To check if the float needs to be aligned, you will want to take the lid off the tank and then flush the toilet. Once the tank refills, check to see if the water level is above the fill level mark. If the water level is above the fill mark, you will need to lower the float slightly. Adjusting the float is usually something you can do on your own, but the process for doing so can vary from toilet to toilet. As such, you may need to hire a plumber if you’re unsure of what to do.

Broken Fill Valve

The fill valve itself can also break or leak, which means the water won’t ever shut off. If the fill valve is broken, you will typically need to hire a plumber to replace it. Nonetheless, a broken fill valve is still something you can typically diagnose on your own.

Again, the fill valve is the plastic tube that the float moves up and down on. To check if the valve is leaking, take the lid off the tank, and then, flush the toilet, and look to see if any water is leaking out around the top or sides of the valve.

If you don’t see any leaks, you will then want to lift the float by hand to see if the water stops running. Lifting the float should trigger the valve to close. If the water keeps running after lifting the float, it usually means that either the tube is cracked and leaking lower down underneath the water level where you can’t see it or the valve itself is broken and won’t close. If you do see any leaks or the water doesn’t turn off after lifting the float, you’ll need to have the fill valve replaced.

Cracked Overflow Tube

The overflow tube is the plastic tube located directly in the center of the tank, which serves two purposes. The first is to ensure that the tank can’t overflow if the water continues running. The overflow tube is also what refills the bowl after flushing. If you look inside the tank, you’ll also see a much smaller, soft plastic tube that leads from the fill valve and drains into the overflow tube. After flushing, a small amount of water drains from the fill valve directly into the overflow tube to refill the bowl.

Although rare, the overflow tube can sometimes crack or break. Should this happen, water will constantly leak through the tube and drain out into the tank. As a result, the toilet will need to run frequently to refill the bowl. Again, the solution to this issue to is to replace the overflow tube. However, this is a slightly more difficult job that you may want to leave to a plumber.

If your toilet is constantly running and you can’t figure out why or get it to stop, the plumbers at TR Miller Heating, Cooling & Plumbing are ready to help. We specialize in all types of plumbing services as well as heating and cooling repairs, maintenance and installation. Give us a call today if you need toilet repairs or any other plumbing or HVAC service in the Plainfield area.

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