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How Do I Test if My Toilet Is Leaking?

How do I test if my toilet is leaking?

Identifying if a toilet is leaking should be done as soon as you suspect a leak, in the interest of saving water and money. Here are some simple steps you can take to test a toilet for leaks:

1. Open the toilet tank
2. Drop a dye tablet or some food coloring in the tank water
3. Wait 15 to 20 minutes
4. After the time has elapsed, look in the toilet bowl (not the toilet tank)
5. If you see colored water in the toilet bowl, you have a leak.

There are other ways to check, if you don’t have food coloring on hand.
• Make sure your water level isn’t above the overflow pipe in the tank. If it is, then you may have a problem with your fill valve.
• If you see water trickling down the inside of the toilet bowl when it hasn’t been flushed, this is a sign of a leak.
• If your unused toilet is making lots of noise (a running noise), then you definitely have a leak.
• If you can jiggle the toilet handle and make the running stop then you probably need to adjust the flapper valve or the chain connecting the flush handle to the flapper valve.

If you think your toilet might be leaking but none of these tests work, there is one last way to determine the problem:
• Before you go to bed, shut the water off to the toilet in question.
• In the morning, check the water level in the tank.
• If there is only an inch of water left at the bottom of the tank, then one or more of your tank parts is bad and is allowing the leak.