Toilet Leaks: 6 Tips on Finding the Leak

Small, silent toilet leaks you don’t even hear can waste over 50 gallons of water a day.  The ones you do hear – a toilet annoyingly turning on and off repeatedly – can waste up to 500 gallons a day. One of the most common household plumbing problems, toilet leaks may have several origins. A cracked tank or base can be seeping water onto the floor behind or beneath the toilet. A worn tank refill valve might be sending gallons of water per hour down the overflow tube. Toilets that mysteriously run only in the middle of the night may even be caused by a spike in the municipal water pressure due to decreased demand after midnight.  

The most common cause of toilet leaks, however, is a worn rubber flapper valve inside the tank. The flapper is what opens when you push the flush handle, sending a surge of water into the bowl to instigate the flushing action. When this valve wToilet Leaks: 6 Tips on Finding the Leakears with age, tank water begins to seep around the edges and leaks into the bowl. As the tank water level gradually declines, the refill valve automatically activates and refills the tank as though it had been flushed. The phenomenon is known as “phantom flushing.”

Here’s a six-step method to track down the source of toilet leaks in your home:

  1. Remove the toilet tank lid and set it gently on the floor.
  2. Flush the toilet and observe the refill valve fill the tank with water, then shut off.
  3. Add about five drops of food coloring in an easily identifiable color such as blue or red to the water in the tank.
  4. Replace the tank lid and wait about a half hour.
  5. Examine the water in the toilet bowl. If it’s clear, there’s no tank seepage. If the bowl water is tinted with blue or red food coloring, you have a leaky flapper valve.
  6. Perform the same test on all toilets in the home to determine if more than one fixture is leaking.

Contact Geisel Heating, Air Conditioning & Plumbing in Elyria, Oberlin or Medina for more help tracking down and repairing toilet leaks.

Our goal is to help educate our customers in Cleveland, Ohio about energy and home comfort issues (specific to HVAC systems).  For more information about toilet leaks and other HVAC topics, download our free Home Comfort Resource guide.

For those Do it Yourselfers who would rather take control of your own indoor comfort, you can shop our online store for replacement parts, products and accessories!    

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