Running Toilet vs. Leaking Flapper

What’s the difference?

This chart provides a side-by-side comparison of a running toilet and leaking flapper.
Additional information about toilets and these problems can be found on our Toilet School page.

CAUSE A toilet is caused when the flapper is prevented from completely closing properly onto the flush valve (it gets "hung-up"). This allows water to run continuously from the tank, into the bowl, and down the drain. This graphic explains how the flapper can get hung-up and why you may not know it. All flappers deteriorate over time. Leaks can also be caused by small pieces of grit or other debris in the tank getting between the flapper and the flush valve, causing the water in the tank to leak into the bowl. For more information about toilet leaks, click here.
COST A running toilet can waste 4.5 gallons per minute, (that's nearly 300 gallons per hour, or 6,480 gallons per day). That could increase your water bill nearly $60 per day. A leaking flapper can waste up to 200 gallons of water per day. That could increase your water bill more than $50 per month.
"Jiggle the Handle" (or turn off the water)

You just need to know when!
A leaking flapper should be replaced as soon as it is detected. When possible, use the manufacturer's recommended flapper, or a universal flapper if an exact replacement is not available. If you are not comfortable making this type of repair, a local plumber can make the repair for you.
HOW CAN THE LEAKALERTOR 6000 HELP? The LeakAlertor 6000 will let you know when the toilet is running, often before you leave the bathroom. The 6000 will continuously beep and flash the red lamp until the flapper is closed and the water begins to refill the tank. The 6000 will automatically return to normal operation once the tank begins to refill. Early detection of a leaking flapper is critical to reducing the amount of wasted water and reducing your water bill. Often times your first indication of a leaking flapper is a high water bill. The LeakAlertor 6000 will quickly detect a leaking flapper, as well as faulty fill valves, and alert you by giving a brief series of audible beeps and flashing the red lamp. (This graphic shows why dye tablets don't work well.)
  • I need more information about how toilets work… click here.

  • I need more information about the LeakAlertor 6000 before I start saving money… click here.

  • I’m ready to stop wasting water and decrease my water bill…