Float Ball
Definition and meaning of Float Ball in real estate.
A float ball is a hollow, buoyant sphere or oval device inside a toilet tank that floats on the surface of the water to control the filling mechanism. It is connected to a float arm, which shuts off the water intake valve once the tank fills to the appropriate level.
In more detail
The float ball is a simple but critical part of a home's plumbing infrastructure, working on the principle of buoyancy. When the water level rises after a flush, the float ball rises with it. Once the ball reaches its maximum height, it applies pressure to the float arm, which activates the shut-off mechanism on the fill valve.
If the float ball develops a leak, it will fill with water and sink, failing to close the valve and causing the toilet to run continuously. Modern toilets often replace the separate float ball and arm with a vertical float cup, but older systems still use this traditional design.
Key facts
| Category | Property Types & Construction |
|---|---|
| Also known as | Toilet float or ballcock float |
| Common materials | Hollow copper, brass, or plastic |
| Watch out for | Cracks or leaks that allow water inside the ball, causing it to sink |
A home inspector notes a cracked float ball that has filled with water and sunk to the bottom of the toilet tank, resulting in a constantly running toilet that wastes water.
Frequently asked questions
What happens if a float ball gets a hole in it?
The ball will fill with water, lose its buoyancy, and sink, which prevents the valve from shutting off and causes water to run continuously.
Can I replace a float ball with a modern float mechanism?
Yes, you can easily replace the old float ball and arm assembly with a modern universal fill valve that uses a sliding float cup.