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The City of Portland, Oregon

Portland Water Bureau

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Fix a Leak Week 2019: Is Your Toilet Flapper Failing You?

A leaky toilet flapper can mean hundreds of gallons of water lost each day. Make sure yours isn’t slacking on the job!

What is a toilet flapper anyway?  The flapper is really the magic behind the flush. This rubber or plastic round cover at the base of your toilet tank allows water to “flush” from the tank into the bowl and down the drain.

What can go wrong with a flapper? Flappers are often the source of potentially costly leaks when they no longer fully seal; flappers typically last about 5 years. There are four ways to check if your flapper is doing its job.

Debris around the seal. If there’s anything (even tiny debris) keeping the flapper from fully sealing, you can get a leak. Water will drain into your toilet bowl from the tank and eventually down the drain!

Chain too loose. The flapper is connected to a chain. As you press down on the flush handle, this chain lifts the flapper to flush the toilet. If the chain is too long, it can get caught under the flapper after you flush, preventing the flapper from fully closing. A loose chain can be tricky because it likely won’t prevent the flapper from closing every time, which could make for an intermittent but substantial leak.

Chain too tight. Just like a loose chain, a chain that’s too tight won’t allow the flapper to close, causing water to leak. A proper chain length will have a slight bend in it and just barely rest on top of the flapper.

Worn out. If your flapper is slick or rough or the material comes off on your hand it’s time to replace the flapper.

Fix a Flapper in Five Easy Steps

You can repair or replace a flapper with these five easy steps. It’s fine to put your hands in the toilet tank water because water in the tank has never had contact with the dirty water in the bowl. Though washing your hands afterwards is always a good idea.

Replacement flappers can easily be purchased at hardware stores and plumbing specialty shops. Take your old flapper with you to make sure you get one that fits. Purchasing an incorrect replacement flapper can result in a leak.

  1. Turn the water inlet shut-off valve clockwise to turn the water off.
  2. Flush the toilet to drain the tank.
  3. Attach the new flapper to notches on either side of the overflow tube base. Hook the chain in a position where it rests without pulling the flapper up or hanging over the edge.
  4. With the new flapper in place, turn the water to the toilet back on.
  5. After installing the new flapper valve, flush to test.
  6. After you flush, make sure that the water level in the tank is at the level indicated on the overflow tube or side of the tank. If no markings are found, adjust tank water level to ½ inch below the overflow tube.

Replace your toilet for a rebate!

If repair isn’t the answer, it might be time for a new toilet. You may be able to get a $50* rebate from the Portland Water Bureau to replace your old toilet with a water efficient model.

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*Single-family residential customers enrolled in the bill discount program are eligible for a $100 per toilet rebate.