Flapper 411

Depending on the extent of the leak, a warped or poorly fitting flapper can waste up to 200 gallons of water a day and may cost hundreds of dollars a year.

A flapper is a rubber mechanism in the toilet tank that is the moving part of the flush valve, sealing water into the tank and allowing water to exit the tank when you flush.

Flappers deteriorate over time because of in-tank cleaning products and chemicals used by utilities. That’s why flappers need to be checked every year to make sure it is fitting tightly over the flush tube. Otherwise, you will end up with a leak that wastes a lot of water and can seriously increase your water bill.

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Is your toilet running?

Getting to the bottom of a leaky toilet can be perplexing. To find out where your leak is coming from, some detective work is probably in order.

To find out if a leak is being caused by the flapper, put a few drops to one teaspoon of food coloring or a dye tablet in your toilet tank. Wait about 15 minutes and if you end up with color in the toilet bowl, you probably have a leaky flapper that needs to be replaced.

Toilet Diagram

How to replace a toilet flapper

Follow these fast and easy steps for replacing your flapper:

1. Close the water supply to your toilet. This is typically located behind the bowl, below the tank. If there’s no valve or the valve is stuck, turn off the water to the house.

2. Flush the water in the tank and note the length of the chain from the flush handle to the flapper. This will save time when installing the new flapper.

3. If the flapper is connected by a circular ring around the tube, remove the refill tube from the overflow tube. (If not, go directly to No. 4)

4. Remove the chain from the flush lever and then remove the old flapper by sliding it up and off of the overflow tube. Or unhook the flapper ears from the overflow tube. For new plastic flush valves, you may have to bend the flapper ears out and off the pins on the flush valve.

5. Write down the toilet manufacturer and the model number if you know it. The manufacturer’s name is often stamped on the outside of the bowl near the seat hinges and the model number is normally on the inside at the back of the tank.

6. Take the old flapper and the information you’ve noted to a plumbing supply store or home improvement store that carries replacement flappers. If you have a 1.6 gpf toilet, the store should have information on the correct replacement flapper and settings for adjustable flappers. Be prepared to pay $2 – $10 for the right flapper. And don’t forget to get a beaded metal flapper chain replacement.

7. Install the new flapper by sliding it down and over the overflow tube until the ring touches the bottom of the tank, with the flapper bulb centered on the valve opening. For plastic valves, cut the ring off the flapper along the lines marked “cut” and slip the ears of the flapper over the pins on the flush valves.