Why Does My Toilet Randomly Run for a Few Seconds?

You may have woken up to find your toilet running while sleeping. Some call it phantom flush, a problem only professionals can fix.

Your toilet may run randomly for a few seconds because of hard mineral build-up, cracked toilet flapper, a caught chain, the float is not lowered, or the refill tube not positioned correctly.

This article will address such issues and teach you how to fix them.

Why Does My Toilet Randomly Run for a Few Seconds?

There are many reasons why your toilet will randomly stop working. One of the most common reasons is that the tank’s flapper is not closing correctly.

It usually arises due to a build-up of hard minerals or sediment in the water. Other possible reasons include the build-up of nutrients.

Flapper Is Not Working Well

If your toilet suddenly stops working and starts to run, a broken flapper could cause this.

The part of the tank that’s supposed to seal drops down usually, and it should be re-sealed once the tank has reached its total capacity. A decaying or cracked flapper allows water to continue running through the tank, and it will enable the water to go back into the bowl.

Chain Is Not Laid Properly

If you’re having a problem with the flapper chain, it could be because it’s getting caught. When you flush the toilet, the lever will pull the chain to remove the flap. If the chain gets caught, the water will keep running continuously.

If the toilet chain is too lengthy or the link is too short, it can prevent it from sealing correctly. It can also happen if the flapper is too short.

Float – Not Lowered

Your toilet may overflow or run continuously if the tank has a high water level. It can happen if the float is too high, which causes the water to soak into the overflow tube. You should lower the float, so the tank doesn’t fill up quickly.

Refill Tube Not Correctly Positioned

When the tube is long, it can cause the toilet to overflow. It happens when the water flows out of the fill valve and into the bowl. The line must be positioned just above the overflow opening if this happens.

Is There a Need to Fix a Running Toilet?

A running toilet is not ideal for the environment, as it can cause a leak and be very expensive. In addition, it can also contribute to the accumulation of toxins.

If you live in a well-watered area, you might be able to drain your resources, but if you live in a city water system, it is simply not something you want to pay for. Also, if your toilet is running, it can cause severe wear and tear much quicker than usual.

How to Fix Your Toilet’s Random Running of Water?

After removing the tank’s lid, turn off the water and flush the toilet. Doing so will allow you to remove any remaining water from the tank. Use a towel or sponge to clean the tank thoroughly.

Examine the Lift Chain

One of the crucial things you can do to stop your toilet from running is to lengthen its lift chain. It will allow you to attach the chain to a rubber disk on the tank.

The rubber disk is the part that holds the flapper. If the chain is not long enough, it will pull the flapper up.

Make sure the chain has around 1 inch of slack around the center. You can easily adjust it by unhooking it from the handle and then re-hooking it back onto one of the links.

Change the Float Ball Inside

If you have dilemmas with your toilet, it could be because the float ball is leaking. A metal or rubber ball usually floats on top of the tank. You can quickly resolve this dilemma by replacing the float ball.

When the ball of the toilet leaks, it will cause it to sink slightly, which will cause it to run. To fix this, remove the ball from the rod and replace it with a new one. Tighten it until it is tight.

Modify the Float Height

You might want to adjust the float height if there is no leak in your flat ball. Doing so will enable you to keep the fill valve open and prevent it from shutting down. This issue can cause the tank to run when it is full suddenly.

If you have replaced your old ball float with a metal one, it may rise along the metal tube. To adjust it, slide it up or down and use the spring clip to compress it.

You might notice a metal arm with an older rubber ball and toilet. You can either fix this by adjusting the set screws on the arm or try bending it.

Wash the Dirt off the Valve Seat

One of the efficient ways to maintain your toilet’s condition is to clean its valve seat. You can do it by removing the sediment deposits.

Models with older tank seats have a metal valve seat. The rubber stop at the bottom of the tank has a triangle shape, and it should seal if it’s not broken. Running the toilet is possible if the toilet stop is not complete.

First, you must train the tank to remove the rubber stop. You can then use a nail file or an emery board to remove any deposits. After doing this, you can put the rubber stop back in its space.

Frequently Asked Questions

Should I Repair or Replace My Toilet Randomly Running?

Sometimes, it’s possible to fix a toilet, while other times, it’s more economical to replace it. For instance, if a running toilet is causing you problems, it might be easier to replace it.

If you have had the same issue with your toilet several times, you might consider investing in a new one. It’s easier to replace the parts now than fix them.

How Important Is Maintaining Your Toilet Correctly?

Maintaining and servicing your toilet is essential to avoid it from getting worn out and eventually causing you to waste water.

Doing so can help lower your water bill and prevent you from experiencing issues with your toilet in the future. Sometimes, you can perform toilet maintenance by adjusting the flow of the bathroom.

There are various causes of a tank’s running issue, and you can determine them by inspecting its components. Doing so can help identify the cause of the problem and prevent it from happening in the future.

Should You Contact Plumber for a Randomly Running Toilet?

If you have a randomly running toilet, you should contact a plumber to fix it. You should also be prepared for the cost of a professional repair job, as it can vary based on the intricacy of the problem and the number of parts involved.

You can start by contacting various local plumbers. They will give you an estimate and recommend a good fix. If you have experience with plumbing, you can usually save up to $200 by doing it yourself.


Some people have a toilet that randomly stops working for a few seconds. It could be because of distinct factors such as a cracked toilet flapper, hard minerals build-up, or the float not being appropriately lowered.

The increase of hard water minerals in the tank’s bottom part prevents it from completely closing, which then causes a slow leak into the bowl. You will activate the mechanism if the amount of water that leaks out exceeds the tank’s capacity.