How It Works
The float assembly is located in the brine well on your softener, and allows water to enter/exit the salt tank. The float is designed as a backup in case the softener ever filled with too much water. In that case, the float would move up with the water level until it reached the top of the mechanism. The water pressure would push the float up against the rubber stopped and ceramic weight on top, in turn closing off the inlet port on the bottom - blocking any additional water from entering the tank.
The float moves freely between two rubber stoppers on the plastic stem. These stoppers are preset to the appropriate heights and do not need be moved during installation or other normal operation.