Why Won’t My Toilet Stop Running?

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Learn How to Fix a Toilet From Running Continuously

A toilet that won’t stop running can be incredibly frustrating. It’s also an obvious indication that your toilet needs fixing. The good thing is that even though there are many possible reasons behind a running toilet, most of them are easy enough to fix.

With that said, this article aims to help you learn why your toilet is running constantly and what you can do about it. And in case the DIY approaches don’t work, you can always call for a professional’s help.

What Causes a Toilet to Run?

Several things could be causing the toilet to run continuously. As soon as you notice you have a running toilet, go ahead and inspect it to see if any of the following components are the reason behind the problem.

Flapper Valve

The flapper valve is a tiny door located at the bottom of the tank. It’s attached to the flushing lever and releases a surge of water whenever you flush. It’s a simple enough material available in different kinds and the most common is rubber.

The rubber flapper valve quickly deteriorates. Over time, they warp and that causes a weak seal. Due to the weak seal, water flows out of the toilet tank into the bowl. Thus, you have a toilet running day and night.

Overflow Pipe

Within the toilet are several parts that control the flush and refill process. One of these components is the float valve, which controls the tank’s water level. Whether your toilet has a traditional ballcock or a floating valve, the fact is it can be set too high.

If the water level is set too high, it can cause the water to rise over the overflow tube. If you don’t know, this tube siphons the water into the bowl to keep it from overflowing. The water level being set too high makes it difficult for the overflow tube to do its work.

Refill Tube

The refill tube is a part of the toilet that connects the fill valve and the overflow tube. If your toilet is running continuously, it could be due to the refill tube that is too long, which leads the water from the tank to go to the overflow valve.

If it’s too long, the refill tube creates a draining effect. It shouldn’t be too long and should only sit above the overflow tube to ensure it doesn’t make the tank run constantly. As a fix, you can use clips to put the refill tube above the overflow tube and prevent the tank from running.

Our resident home repair guru, John Turpin, has provided a list of common reasons why your toilet won’t stop running, along with some suggested solutions and DIY tips to fix it.

Flapper Chain

Another issue related to the flapper is the chain. The flapper chain must be long enough that it reaches the flapper valve. It should also be slightly slack. If it’s too short, then it might not be able to create a proper seal.

The chain can’t be too short, but it also can’t be too long. It can’t have too much slack or the chain goes under the valve, leading to leaks getting through. Keep the slack slight, just around half an inch, to ensure it works without a problem.

Flushing Handle

The flushing handle is what triggers the flushing and refilling of the toilet. If it’s faulty, it sure could lead to the toilet running. The fact is that the handle corrodes after some time, especially older handles made of metal.

When the handle becomes corroded, it often ends up staying in the down position. As a result, the flapper valve is forced inside the tank, causing it to stay open. This situation leads to the toilet running continuously to try to fill the water tank.

Toilet Gaskets

Most toilets today have the tank and toilet bowl molded separately, which is known as a two-piece model. Gaskets are used to attach these two parts when installing the toilet. The gaskets are made of thin rubber, which is about the only thing that prevents water from leaking.

Over time, the gaskets wear out and when that happens, the toilet will be running continuously to keep the tank filled. The solution would be to buy a new gasket and replace the old one. The good news is you should be able to replace the gasket yourself.

Fill Valve

The fill valve delivers water to the tank taken from the supply line, which is the beginning of the refill process. It obviously plays an important role in the way a toilet works, which means a damaged fill valve can cause a running toilet.

The fill valve is just as susceptible to damage as other parts of the toilet. Do you think your fill valve is the root cause of your toilet that continues to run? If it is, know that it’s a bit complicated to replace a fill valve. If you’re not sure about a DIY approach, better call an expert instead.

How to Fix a Running Toilet

The steps to fixing a running toilet depend on the root cause of the problem. As such, the first thing you need to do is inspect it and locate the actual cause of the constantly running water. If it’s the flapper valve, flush valve, or fill valve, you can try the following troubleshooting tips.

Overflow Tube

If the problem has to do with the overflow tube, try these steps:

1. Start by checking the water level and making sure that it is below the fill valve and overflow tube. This way, the water doesn’t flow constantly into the tank and out to the overflow tube.
2. Adjust the float cup or float rod to lower the water level in the tank. It’s a horizontal rod that extends from the fill valve to the float ball. To turn it, find the screw that attaches it to the fill valve then move counterclockwise, making adjustments until the water is below the overflow tube.
3. Check that the overflow tube isn’t too short. If it is, you will need to change the flush valve to fix the issue.

Flush Valve

If the problem is with the flush valve, try fixing it by following these steps:

1. Check the chain. As we mentioned before, the chain can’t be too short or too long. Make sure that it’s the right length so that the flapper can close and open fully, without any issues.
2. Inspect the flapper next, confirming it is not worn, warped, dirty, or sitting wrong in the flush valve seat. If you find any defects, you should replace the flapper. If it’s only dirty, cleaning it with a water and vinegar mixture should do the trick.
3. If the toilet still runs after dealing with the chain and the flapper, it might solve the problem if you replace the flush valve. Remove the old flush valve and install a new one, making sure to tighten it and replace the gasket as well.

Fill Valve

Another way to fix a running toilet is by repairing the fill valve. First, confirm that nothing is wrong with the fill valve. The fill valve is likely the problem if water continuously overflows but you’ve confirmed that the water level is just an inch below the overflow tube and the tube is at the right height for the toilet. If you find the fill valve is defective, you will need to replace it. Do it like this:

1. Turn off the water to the toilet then drain the tank. Make sure there’s no excess water left by disconnecting the water supply line.
2. Take out the old fill valve by unscrewing it from the bottom of the tank. Install the new fill valve while ensuring the height suits the toilet’s tank and water level.
3. Thread the end of the valve into the tank and secure it with the locking nut. Don’t forget to reconnect the water supply line and check if the fill valve is working.

If these troubleshooting tips didn’t work and you still have a running toilet, you should call a professional plumber right away. They will be able to figure out exactly what’s wrong with your toilet and how to resolve your problem before it causes water damage.

Hire a Local Plumbing Pro

The methods above are effective DIY tips to investigate, diagnose, and fix why toilet won’t stop running. But if you need professional help, then don’t hesitate to contact a local plumbing pro using the phone number or form on this page.