Last Updated: September 14, 2020
It’s the last sound you ever want to hear in your bathroom: the endless flush. Your toilet is supposed to stop refilling, but instead just keeps going, no matter how much you jiggle the handle. Endless flushes can render your toilet useless while wasting hundreds of gallons of water every day.
The endless flush is a problem with a part called the “flapper,” an unassuming bit of rubber that sits at the bottom of your toilet tank. Understanding what can go wrong with the flapper is an important step toward being able to fix your own plumbing problems. Today, we’re going to boost your toilet literacy by going over the five different types of toilet flappers.
How Flappers Work
Toilets rely on the flapper to start and stop the flushing process. The flapper seals off the pipe leading into the bowl. When you pull the flush handle, it rises to allow water to flow into the bowl, then closes again when the flushing process is complete.
When working perfectly, most flappers will close after a short time because of the weight of water in a reservoir — either one that’s filling up (rubber flappers) or draining out (seat disk flappers). However, flappers are vulnerable to deterioration and decay, since toilet water contains chemicals that can wear away at plastic and rubber over time.
When a flapper can no longer seal off the pipe, the toilet no longer “knows” when to stop flushing, and that’s when you get the endless flush. It’s best to replace the flapper before you get to that point.
How to Spot a Worn-Out Flapper
The best way to know when it’s time to replace your flapper is to inspect it. Don’t be afraid to reach into your toilet’s tank — that’s the same water that comes out of your taps!
Check to see if any part of the flapper has deteriorated. Inspect the seal for leaks. Look at the connection between the flapper and the chain or lever that connects it to the flush handle: that’s often the first thing to go.
If the flapper looks all right, but you still aren’t sure, try the food coloring test. Put three drops of food coloring into your tank, then wait for 20 minutes without flushing. If you see any color in the bowl after 20 minutes, it means your flapper is leaky, and needs to be replaced.
Make replacement your priority if your flapper fails the food coloring test. At that point, it’s already driving up your water bill.
The 5 Types of Flappers
Just by looking at your flapper, you can learn a lot about how it works, and how you’ll need to replace it. Ideally, you’ll want to replace your flapper with the same kind that’s already in there. However, you have a bit of flexibility, as you’ll see.
Two main traits differentiate the types of toilet tank flappers: shape and adjustability.
1. Seat Disk Flapper
The oldest toilets still in use flush using seat disk flappers. This design centers on a large disk that’s connected to a reservoir full of water.
When you pull the flush handle, a system of levers raises the disk to allow water into the bowl, while the weight of the reservoir keeps the disk open. In the open position, the reservoir drains slowly, eventually becoming light enough that the disk falls shut. The reservoir then refills.
There’s a reason seat disk flappers aren’t used much in newer-model toilets. They’re convoluted, bulky, and inefficient — after all, the more parts a system has, the more potential ways it can fail. However, if you do have one of these, companies like American Standard still sell replacement parts.
2. Tank Ball Flapper
Almost all toilet tanks have a float-ball or ballcock that’s responsible for stopping the flow of new water into the tank. Tank ball flappers apply the same principle to filling the bowl.
Tank ball flappers are connected to the flush handle by either a rod or a chain. Instead of being perfect spheres, they usually feature a large bowl that fills with water during the flushing process. When this bowl is heavy enough, the flapper sinks and seals the outflow pipe.
At least, that’s what is supposed to happen. If the tank ball is connected to a chain, it often fails to seal the pipe if the chain isn’t exactly the correct length. Tank balls connected to sturdy rods work better; however, this kind of mechanism never caught on, and isn’t found in many tanks.
3. Non-Adjustable Rubber Flapper
Rubber flappers are far and away the most popular design in modern toilets. Unless you live in an old, unrenovated building, it’s almost guaranteed that you have one of these. The final three types of toilet flappers are variations on this theme.
A single piece of rubber is connected by a hinge to the overflow pipe, and by a chain to the flush handle. A hole in the flapper gradually fills it with water, eventually closing it by its own weight. It’s a simple, efficient mechanism with very few points of failure — before the material itself starts disintegrating.
Some rubber flappers are adjustable. You can decide for yourself how long the flush will last: shorter flushes save water, while longer flushes get rid of more waste. The basic type of rubber flapper is not adjustable but can be replaced with a flapper that is.
4. Rubber Flapper with Floater
One way to make a rubber flapper adjustable is to attach a floater to the chain. Depending on where you move the floater up and down the chain, the flush will allow more or less water through the drain before closing.
5. Rubber Flapper with Control Dial
On some flappers, you can adjust the flush length using a dial built into the rubber piece itself. Turning the dial one way will use more water and turning it the other way will use less.
Other Tips for Choosing a Replacement Flapper
In addition to the various shapes they take, flappers come in multiple different sizes. Fortunately for DIY toilet repair, it’s easy to determine the measurements you’ll need.
Toilets are sized based on the diameter of their pipes. A toilet with a pipe two inches across is called a 2-inch toilet, three inches makes a 3-inch toilet, and so on. To find this out, measure the diameter of the seal on your flapper. If you’re not comfortable with your measurement, though, you can always just remove your old flapper and take it shopping with you.
You should also pay attention to what the new flapper is built out of. Almost all new flappers are made of waterproof materials that won’t rust, such as rubber or plastic.
However, rust and water damage aren’t the only problems a flapper faces. The warm, wet environment of a toilet tank is the perfect place for mold to grow, and mold can deteriorate some materials over time. Consider buying a replacement flapper that’s treated to resist mold and mildew — it might last longer.
Good luck: if you’re patient and diligent, that endless flush won’t be endless for long!
Featured Image Credit: Warren Price Photography, Shutterstock
Image credits: Amazon.com