Anatomy of an American Toilet

I doubt anyone but me cares, but I was so intrigued with Brilly's comment about her toilet having two buttons (how do the button's work--is the toilet electric?), I felt inspired to photograph my toilet and discuss the parts, even though I don't know for sure what they are called, but I sort of know what they do.

I did mark letters and little red arrows on the pictures, so to see them, you'll probably need to click on the image to make it larger.

A is my flush handle on my toilet. It is purely a mechanical lever. When you push it down, inside, a metal "beam" goes up. The inner "beam" I'll call a lever is item C on the first toilet tank gut picture and is I on the second picture. I took shots of both my toilets because I was stunned to find my new toilet (the one shown in the original picture) has the float ball mechanism (B). I thought those only came in old toilets. I had to go shoot other toilet to show the fluid master valve assembly (J).

Item D is a post that has a flapper connected at the bottom. I couldn't get that in the shot. Item G is the flapper in the second toilet. H tries to show the chain that connects the lever to the flapper, but the angle is poor. The flapper is what lets the water out of the tank (because the lever lifts it) and into the bowl when one flushes and then goes back into place to seal the tank off from the bowl so it can be refilled. Items F and E are the water lines (refill tube) that bring in the fresh water after you flush. They are ultimately connected to the fill line to the toilet at the bottom of the tank.

In the first toilet, the float ball rides on top of the water as the tank refills. It's arm is connected to a shut off mechanism. When the ball rides high enough on the water, the water supply cuts off. In the second picture, there is a floating piece that rides up a post and shuts the water off when it floats high enough.


1. You push the lever on the outside of the toilet.

2. It acts as a lever that mechanically lifts the flapper valve and lets water drain from the tank into the toilet. That surge of water makes the material in the toilet bowl go away (down the drain) and then refills the bowl with some water. As the tank empties (water level drops), the floating mechanism drops, opening the valve that allows the water to fill the tank.

3. When the tank empties, the flapper valve falls back into place, sealing the tank from the bowl.

4. The water continues to fill the tank until the float mechanisms are high enough to shut the valve that fills the tank with fresh water.

I'm guessing Brilly's toilet is very similar except somehow she has a different kind of mechanism to raise the flapper valve since hers has a button. Why two buttons? Maybe one is for little business and the other is for big business (one dumps half the tank into the bowl and the other drops the entire tank into the bowl).

Probably more important than any of this is why on Earth am I so interested in the mechanics of a toilet? All I can say is it might be that same lump of curiosity that drove me into engineering in college, or perhaps it is merely the desire not to have to pay a plumber any more than is necessary, especially considering I am now responsible for the functioning of two toilets at my house, and a total of eight more in our rentals.