SAWS: Toilet Leak? - Flapper Fix
Aquifer Beaker

Edwards Aquifer

Aquifer Level 685.4'
11/15/18 - Official

The Edwards aquifer and its catchment area in the San Antonio region is about 8,000 square miles and includes all or part of 13 counties in south-central Texas.

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Year-Round Watering Hours

Watering with an irrigation system or sprinkler is allowed any day of the week before 11 a.m. or after 7 p.m.

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Aquifer Level 685.4 | Year-Round Watering Hours

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Do-It-Yourself Repairs

Replacing Your Flapper

Steps for replacing your toilet flapper

Step 1
Turn off water to tank at the customer shut-off valve to the house.

Step 2
Flush the water in the tank. Note: the length of the flapper chain attached to flushing handle.

Step 3
Remove old flapper.

Step 4
Write down model of the toilet. Also note if toilet is a 1.6 gpf (gallon per flush) model. If the year of manufacture is before 1992, it most likely is not a 1.6 gpf toilet.

Step 5
Take the old flapper and its information to a plumbing supply store. If your toilet is a 1.6 gpf model, purchase a flapper that keeps the flush at 1.6 gpf.

Step 6
Be prepared to pay $2 to $10 for the correct flapper. Make sure you purchase the right flapper for your toilet. Installing the wrong flapper or a generic one could cause your toilet to use much more water than necessary.

Click here to find the right match for your toilet model.

Step 7
Install the new flapper. Adjust the chain as it was before you removed the old on. Turn on water and perform a test flush. Make water level and chain adjustments if needed.

Visit Replacement Flappers to find the right match for you toilet model. Settling for a one-size-fits-all flapper can quickly turn your water-efficient toilet into a water waster.

Note: Replacing a flapper or fill valve is not a difficult process. However, if you do not feel comfortable performing the following steps, we recommend that you hire a licensed professional plumber to do the work for you.

Tools needed:

  • Adjustable wrench
  • Awl
  • Flathead screwdriver

Checking for Leaks

It is very simple to check for a leaking flapper and leaking fill valve:

  1. Remove the tank lid. (Don't worry. The water is clean until it enters the bowl.)
  2. Once the tank is fully refilled after a flush, add some food coloring or a dye tablet. Put the tank lid back on.
  3. Don't flush the toilet again until after inspecting the toilet bowl.
  4. After about 30 minutes, look in the bowl. If you see colored water, you have a leak.

Why the Leak?

When the flapper (flush valve) fails to seal properly, water leaks from the tank into the bowl. The lost tank water is replenished by the refill valve, causing a continuous flow of wasted water.

If the refill valve leaks, the tank overfills and the excess water runs from the overflow pipe into the toilet bowl.

Fill Valve

To replace the fill valve in your toilet, follow the instructions found in the packaging you purchased.