How a Toilet Works
The three main systems that work together in a toilet to enable the flushing process are the bowl siphon, the flush and refill mechanisms.
The Bowl Siphon
The bowl siphon is molded into the toilet bowl. Once a 2 gallon water surge fills the siphon tube, this mechanism will automatically be activated and suck waste out of the bowl and into the sewer pipe. As the bowl empties, air enters the siphon tube, stopping the siphoning process.
The Flush Mechanism
The flush valve is connected to a chain attached to the flush handle. Pushing the flush handle will cause the attached chain to lift the flush valve and reveal a 2-3inch diameter drain hole through which water enters the bowl. Most of the water will flow directly through a hole at the bottom of the bowl known as the siphon jet, and into the siphon tube to activate the siphoning process.
The Refill Mechanism
Once the tank is empty, the flush valve drops to the bottom of the tank to cover the drain hole and allow the refilling of the tank. The job of the refill mechanism is to fill the tank with enough water to activate the next siphoning process.
How a Toilet Works: Putting it all Together
1. Pressing the flush handle pulls the chain which lifts the flush valve.
2. About 2 gallons of water empty from the tank into the bowl in about 3 seconds.
3. The quick surge of water activates the siphoning process in the bowl. The siphon sucks waste out of the bowl down the sewer pipe.
4. As water is rushed out of the tank, the flush valve falls to cover the drain hole. This activates the refilling process of the tank and bowl.
5. As water levels rise in the tank so does the flush valve up to a certain level at which point the refill valve shuts off.
6. If the refill valve keeps running, the overflow tube will be activated to stop overfilling of the tank.