Why is My Toilet Double Flushing

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Have you noticed that when you flush your toilet, it flushes normally then after your bowl fills with water, the toilet spontaneously flushes itself a second time? Your toilet could be having a problem called double flushing. When your toilet double flushes, water is wasted, and your toilet could be damaged.

However, it's normal to feel frustrated when your toilet starts double flushing, especially if you don't know where the problem is coming from. Here are the most common reasons for a double flushing toilet and how you can fix them:

How Your Toilet Works

Toilets have two main parts: a bowl and a tank that works in a simple mechanism. Most flush toilets are gravity flush toilets. This means that water flows from the tank to the bowl using gravity, and when it gets to the bowl, a siphon effect is created that sucks the waste from the bowl to the drainpipe.

How Your Toilet Works
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You may have a single flush or dual flush toilet. A dual flush toilet uses flush buttons to flush, while a single flush toilet uses a trip handle located on the side or front of the tank. A dual flush toilet doesn't have a toilet and will hardly flush twice compared to a single flush toilet.

Here are the toilet's parts that enable it to function efficiently:

The Toilet Handle

This is where the flushing process starts. It's located outside the toilet tank but has a long arm that goes outside the tank. To flush the toilet, you'll need to push the toilet handle down.

Lift Chain and Flapper

When you flush the toilet, the handle lifts a chain that's connected to the toilet handle arm and hooked on the flapper. When the toilet isn't in use, the lift chain is normally slack. When you push the handle down, the chains pick up some tension and lift off the toilet flapper.

The Toilet Flapper

If you're experiencing a double flush in your toilet, then this might be the main culprit. It's a piece of the rubber seal that sits at the top of the flush valve opening. It prevents water from running into the bowl all the time and will open only during flushing.

The lift chain pulls on the flapper when you push the flush handle down, opening it up. Water then flows through the flush valve and into the toilet bowl. The flapper will then fall back into place, sealing off the flush valve opening.

The problem with a double flush occurs when the flapper doesn't completely seal off the flush valve opening. This can happen for a number of reasons. The most common is that the flapper isn't seated correctly on the flush valve opening. This can be because the flapper is old and worn out, or it might be the wrong size for your toilet.

Reasons for a Double Flushing Toilet and How to Fix Them

The Flapper Is Stuck Open

The flapper is the rubber seal that covers the hole at the bottom of your toilet tank. When you flush your toilet, the flapper lifts to allow water to flow from the tank into the bowl. If the flapper is stuck open, water will continuously leak into the bowl and cause your toilet to double flush. If your toilet keeps flushing or flushing twice, then you need to check your flapper.

The Flapper Is Stuck Open
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If the toilet flapper also stays up for too long, it's because your toilet has been fitted with a generic or universal flapper instead of the specific flapper designed for your toilet model. Generic or universal flappers are often too lightweight to drop securely back into place after a flush. These aftermarket flappers don't always provide a perfect seal and may cause your toilet to double flush.

If the flapper valve isn't adjusted to the correct amount of water, excess water will be allowed into the toilet, forcing it to flush for a second time. To fix this, take the tank lid off and flush the toilet. Check to see if the flapper closes by itself or does it stays open for a while.

If the toilet flapper stays open, then that's what is causing the double flush. If you have an adjustable cone flapper, try turning the dial on top of the flapper. This will open up larger holes on top of the flapper, which releases air caught inside of the flapper, making it less buoyant.

If your flapper isn't adjustable, then you'll need to replace it with the heavier model to solve the problem. If the toilet flapper closes by itself, then there might be something else causing your double flush. Try gently pressing down on the handle while the tank is filling up with water. If this stops the double flush, then you might need to adjust the float cup.

Your Toilet May Flush Twice Because of Too Much Water in the Tank

If your toilet tank is filling up with too much water, then it will cause the toilet to flush twice. The first flush occurs when the float cup drops too low and allows the flapper to close. The second flush happens when the float cup rises back up, opening the flapper and allowing more water to enter the bowl.

When your fill valve is also set improperly, you'll hear the tank water running after each flush. If you need to adjust the float cup, turn off the water at the shut-off valve and flush the toilet to empty the tank. Then, remove the lid and use a flathead screwdriver to loosen the locknut that secures the fill valve to the tank.

If your toilet fill valve has a float arm, take a screwdriver and adjust the screw on top of the fill valve to lower the float arm. If there's no adjustment screw, then you have an old fill valve, so you need to replace it. Contact a professional plumber to install a new fill valve float arm. Some fill valve models also have a water level adjustment rod, which you can turn to lower your toilet tank's water level.

FAQs on Why Your Toilet is Double Flushing

How to fix a double flushing toilet?

The first step is to determine the root cause of the double flushing. Once you know the reason your toilet is double flushing, you can take steps to fix it. If your toilet is double flushing because the water level in your tank is too high, you can adjust the water level by turning the water level adjustment rod. If ypou have an old toilet leading to this problem, consider investing in some of the best flushing toilet on the market.

Why is my toilet double flushing?

Your toilet could be double for these two reasons: the flapper may not be working properly, or there may be too much water in the tank. If the flapper isn't working properly, it may not be sealing the tank after each flush, causing water to constantly enter the bowl.

If there's too much water in the tank, it will constantly enter the bowl and cause the toilet to flush twice. The best way to fix a double flushing toilet is to adjust the water level in the tank. You can do this by turning the water level adjustment knob.

Final Thought on Why Your Toilet is Double Flushing

Your toilet double flushing is normal that you don't need to panic about. In most cases, it can be easily fixed by adjusting the water level in the tank. If you're still having trouble, you may need to replace the flapper. If you don't feel comfortable doing the repairs and replacement, consider calling a professional plumber.


Kristina Perrin

Kristina Perrin

Kristina is an expert DIY home remodeler and mom to three. When she's not cooking or experimenting with new recipes, you can find her working on new home improvement projects or writing about her favorite kitchen appliances or DIY projects on Kitchen Infinity blog.

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