Toilet Tank Fill Valves

How a Toilet Tank Fill Valve Functions

By Mark J. Donovan

Have you ever wondered how your toilet operates? Besides the tank and bowl, it is the toilet tank fill valve that is the most important item in the toilet.

The toilet tank fill valve, as its name suggests is responsible for filling the toilet tank with water and causing the toilet to flush.

The toilet tank fill valve is located on the left hand side of toilet tank, and works in conjunction with a float that is connected on the end of the toilet tank valve rod. 

When you push on the toilet lever the toilet flapper is lifted up and water begins to drain from the tank into the bowl causing the flushing action.

Simultaneously the toilet tank fill valve begins to refill the tank with water as the toilet flapper closes. As the water drains from the tank, the float sinks to the bottom of the tank, and in the process activates the switch in the toilet tank fill valve to begin refilling the tank.

Once the water has reached a certain level in the tank, the toilet tank fill valve switch shuts off.

Frequently you can bend the rod that connects the toilet tank fill valve to the float, so that more or less water can be stored in the toilet tank.

Toilet tank fill valve.

By having more water in the tank you can create a stronger flush, and alternatively by having less water in the tank you can produce a weaker flush.

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