If you hear odd noises when you flush your toilet, it runs constantly, or it takes a couple of times to clear out the bowl, you may need to fix the toilet fill valve. This valve controls the refill of water in your tank after you flush. Fixing a toilet fill valve (once referred to as a ballcock) is relatively easy to repair if you have a standard Fluidmaster brand valve.
Often, a fill valve is repaired by simply replacing the entire fill valve, but Fluidmaster fill valves can be corrected by just replacing a seal inside the unit. If your Fluidmaster fill valve is not shutting off all the way or not filling quickly like it did when it was new, then replacing or cleaning the fill valve seal will most likely fix the problem.
How to Test Your Toilet Fill Valve
When your toilet is constantly running, the culprit is usually one of three things—the toilet fill valve, the float, or the flapper. The best way to tell if your fill valve is the problem is to remove the lid from your tank and observe what's going on as you flush the toilet. Do you notice a leak coming from any part of the fill valve? If not, lift the arm attached to the float as the tank fills up. When you lift the arm, the water should stop. If the water does not stop, there is likely something wrong with your fill valve, and a leak is happening inside the fill valve.
How Often to Replace a Fluidmaster Toilet Fill Valve
The manufacturer recommends replacing the entire valve or parts every five years to avoid flooding that could damage your home. If there's rust above the water line or rust or discoloration on the top cap lever arm assembly attached to the adjustment rod, it's strongly suggested that you replace the entire fill valve.
How to Repair a Fluidmaster Toilet Fill Valve
Equipment / Tools
- Mug or cup
- Protective rubber gloves (optional)
- Fluidmaster valve replacement seal
Find the Shutoff Valve
Locate the shutoff valve that controls the water supply to the toilet. The shutoff valve is usually located on the wall below the toilet tank and has a small handle. The valve will be connected to a water supply tube leading to the bottom of the toilet tank.
Turn off the Water
Shut off the water to the toilet by turning the handle on the shutoff valve clockwise until it stops.
Flush the toilet to remove most of the water in the tank.
Take off the Plastic Cap
Loosen the plastic cap on the top of the fill valve: Wrap one hand around the fill valve shaft, then slide it up to push the float cup (the large plastic cylinder that slides on the valve shaft) up towards the top of the fill valve, and grasp the shaft firmly.
Use your other hand to turn the cap on top of the fill valve counterclockwise 1/8 of a turn. It may help to push down on the cap while turning.
Lift the cap from the top of the valve and set it aside. The valve seal is inside the cap.
Position a Mug
Place a mug or drinking cup upside down over the top of the valve and hold it in place with one hand.
Flush the Shutoff Valve
Use your other hand to carefully open the shutoff valve by turning it counterclockwise. Water will flow out of the fill valve, into the cup, and then down into the toilet tank. This flushes any debris from the valve.
Close the Valve
Now close the shutoff valve by turning clockwise until it stops.
Take off the Old Seal
Then remove the old fill valve seal from the valve cap.
Position the New Seal
Install the new valve seal, fitting the nipple on the seal over the stainless steel needle in the cap so the nipple goes up into the cap; this should match the orientation of the old seal.
Put on the Fill Valve Cap
Reinstall the fill valve cap by fitting it onto the valve as before and turning 1/8 turn clockwise to lock the cap in place.
Turn on the Shutoff Valve
Open the shutoff valve slowly turning counterclockwise until the handle stops.
Refill the Tank
To finish the job, let the valve refill the toilet tank, then flush the toilet, and check the operation of the fill valve. Also, check for any leaks at the shutoff valve.
Cleaning Tips for a Fluidmaster Toilet Fill Valve
- Clean the valve of calcium or mineral build-up by dissolving it with vinegar applied with an old toothbrush. After the surface is clean, wash the valve with warm soapy water, then rinse.
- Once a year, or if the fill valve will not turn off, remove the cap assembly and inspect the valve for debris. Place an inverted cup over the uncapped valve body and turn the water on for a few seconds to rinse out the valve. Remove and clean the seal and the cap. Then reinstall parts in the tank.
- If you use bleach tablets to clean your bowl, inspect your tank more frequently. The bleach tablets may erode your toilet fill valve and seal.
How often will a Fluidmaster toilet fill valve need replacement?
How difficult is it to change a Fluidmaster fill valve on a toilet?
Is it expensive to change a Fluidmaster fill valve?