What Does It Mean When Your Toilet Sounds Like It Randomly Flushes?

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A toilet does not actually flush by itself, even though your toilet makes flushing noises when nobody is in the bathroom at the time. A malfunctioning problem in a toilet that's caused by a faulty part, such as a worn-out flapper valve, or a mechanical problem, such as loose toilet bolts, can cause it to sound as if it is being flushed by an unseen force. Once you understand what causes the flushing noise, you'll be able to isolate the source of the problem and provide a solution.



When a toilet sounds like it's randomly flushing, it's because the water level in the tank lowers to a level that triggers it to refill with water.

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Phantom Flushing Noise

When your toilet sounds like it randomly flushes, even though nobody is near the toilet, it is referred to as phantom flushing. Despite the name, when a toilet phantom flushes it does not actually flush.

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The sound you hear that sounds like flushing is the tank refilling with water that has been lost, which you hear after you flush a toilet. A leak in the toilet's tank or an improperly seated or worn-out flapper valve, not paranormal events in your house, causes phantom flushing.


Phantom Flushing Wastes Water

While phantom flushing may scare you as you are startled by the sudden sound or annoy you as you continually hear the noise of the toilet's tank refilling, even more important, the phantom flushing toilet wastes water. The constantly refilling toilet tank will lead to a higher water bill as your household water usage increases.


How often the phantom flushing occurs affects how much it will raise your water bill. Beehive Plumbing notes that a constantly running toilet, even from a slow leak, has the potential to waste 200 gallons of water each day.

Detecting the Source

Before you can fix a phantom flusher, you must first determine the source of the leaking water. You need to remove the toilet tank's cover and gently place it aside. Once the toilet is idle and not making any noise, place 10 drops of food coloring into the tank's water, as suggested by Ask the Builder.


The key is to use a dark food coloring that is easy to see in the water. Several moments of waiting and watching will show you where the water is leaking out of the tank, since the food coloring will be pulled to the site of the leak.

Fixing the Problem

One of the most common causes of phantom flushing is a worn-out flapper valve in the toilet's tank. Replacing a toilet flapper involves removing the old flapper and installing a new one.


You must also adjust the flapper's chain so it allows the flapper to sit down securely over the drain opening, but not so long that it binds up. If you find that water is leaking out at another point, such as the bolts in the bottom of the tank, tighten the part where the leak is occurring or replace the parts.




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