What Is a Float Valve?

You probably have more than float valve in use in your home right now. They are very simple devices that are very accurate and highly reliable.

Function

A float valve has one purpose--to stop the flow of water in an inlet supply line. This is done with a float device that rises with the water level in the reserve tank and will cause the valve to be activated.

Time Frame

The float valve (ballcock) was patented by Thomas Crapper for use in the toilet around the turn of the century. Since then is has been in use in nearly every toilet in the world and remains in use today. (Thomas Crapper is often wrongly credited with inventing the toilet, he did not. He did make improvements to its design, which probably accounts for the error.)

Features

A float valve has three primary parts. The valve, a stem and a float device. The valve is attached to the float device by the stem. This will regulate when the valve is opened and closed.

Operation

When the water in the reserve drops, the float device drops as well. This opens the valve and water begins to re-fill the tank. As the water rises so does the float device, which will eventually shut off the valve when it reaches the proper height.

Reliablity

The simplicity of the design allows the float valve to operate very efficiently and accurately over a long period of time. While the design has been modified, the original concept and function remains very much the same.