How Does a Toilet Work When You Flush?

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These days, having a functioning toilet inside of your home isn’t exactly anything to jump up and down about.  It’s just kind of a fact of life now, but we should remember that indoor plumbing, and toilets especially, weren’t always a part of everyday life.  So, if you’ve ever wondered how the modern marvel of a toilet works, we’re breaking the process down and looking at the complex inner workings of one of the most innovative and important plumbing fixtures in your home.  

How Does a Toilet Work?

The Bowl Siphon

Despite having no moving parts, the toilet bowl features a highly functioning design.  The most crucial piece of the toilet is what is molded into the bowl, and it is known as the bowl siphon.  The bowl is attached to a pipe with a U-bend that leads into a sewer system.  As water and waste leave the bowl when you flush, air rushes in causing the “flush” sound, and that air coming into the bowl is what stops the siphoning process.  Once gone, the bowl is then refilled with water from the tank.  

The Toilet Tank

The tank that is located in the upper part of the toilet holds about two gallons of clean water.  It can send the water fast enough into the bowl to activate the siphon effect (or flush) and send waste and water down the pipe in a roaring “whoosh!”

This occurs when you push the handle down.  The tank system is activated causing water to dump into the bowl in less than three seconds, triggering the flush.  The same effect can be achieved by the siphon alone as long as you pour enough water quickly into the bowl (a trick that can come in handy if you ever lose power for an extended period of time).  

What Happens Inside of the Tank?

Once you push the handle, the chain that is connected to the flapper and flush valve is pulled up by the handle arm.  By lifting the flapper up, the water inside of the tank is allowed to flow down into the toilet bowl.  As the water leaves the tank and enters the bowl, it fills the toilet bowl, and the siphon effect occurs, removing water and waste.  

As the tank is emptied, the flapper covers the drain hole, and water comes into the tank to refill it.  And thus, the mystery of the flush is revealed!

Unique Toilet Tank Functions

The Float Ball

The float ball is connected to the fill valve that controls the water flow to the tank.  When the water reaches a certain level in the tank, the ball floats level on the water, shutting off the refilling mechanism.  When the tank is empty, the float ball falls freely allowing the valve to open, filling the tank.

The Refill Tube & Overflow Tube

The refill and overflow tube work together to help keep water in the tank.  The overflow tube empties directly into the toilet bowl below, refilling the bowl after each flush.  If there were no refill tube, there would only be a small amount of water in the bottom of your toilet which could become a bit of a problem.  

The Flapper

The flapper is a rubber mechanism that acts as a seal to the drain.  It both lets water in and out of the tank when you flush.  

All of these intricate parts work together to perform, what we’ve become accustomed to, such a seemingly simply act.  But, as we hope you can now see, your toilet is so much more than a modern amenity; it’s a high-functioning machine.  So, next time you flush, don’t throw to waste your gratitude.  

By | 2018-02-04T20:28:42+00:00 February 8th, 2018|Bathroom Plumbing, Blog|Comments Off on How Does a Toilet Work When You Flush?

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