Fluidmaster is a company that specializes in the sale of toilet parts and accessories. Fluidmaster parts are designed to improve the flushing and filling functions of your toilet, minimize the risk of both internal and external water leakage and give toilet owners better control over the settings of their toilets. Fluidmaster parts do this all while maintaining an easily adjustable design. As a result, if your toilet contains a Fluidmaster 400 model of universal fill valve, it's an incredibly simple task to adjust it and solve the problem.

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How to Adjust a Fluidmaster

Fluidmaster Fill Valve Function

Some of Fluidmaster's best-known products are its line of universal fill valves. The fill valve is the component of a toilet that controls the amount of water pulled into and held inside the toilet's tank. Some fill-valve models come with a Fluidmaster leak guard that attaches to the flapper and float system in control of releasing water from the tank into the toilet bowl. This system, attached to the toilet's fill lever, acts as a secondary seal. If the leak guard is triggered by an excessive loss of water in the tank, it stops the flow of water.

Fluidmaster Fill Valve Adjustment

Fluidmaster fill valve adjustment can be done by hand without removing the part from the toilet. This long, dark-colored tube will have a screw to its side; this can be adjusted either by hand or with a Philips-head screwdriver. One full turn counterclockwise will decrease the water level in the tank of your toilet, while a full clockwise turn will increase it. To prevent external flooding, it is advised to maintain a tank water level that is at least one inch lower than the toilet's handle. This will allow your toilet's overfill pipe to work properly in the event of a stoppage.

Adjusting Fill Valve Leak Guards

If your Fluidmaster fill valve has a leak guard attachment, adjusting it is very similar to the procedure you would take when adjusting a toilet flapper's floater. To adjust the level at which the leak guard triggers, merely shorten or lengthen the chain used to connect the guard to your toilet's fill lever. Shortening the chain will make the leak guard more sensitive to potential leaks, while adding slack to the chain will allow the system more leeway. This chain can be adjusted by using a pair of pliers to unclasp the chain and then adding or removing chain links as necessary.