How to Replace a Toilet Float Valve

Check the float valve if your toilet is malfunctioning.

The toilet float valve, also known as the fill valve, is the part of the toilet's plumbing that regulates how much water enters the tank. When you press the flush handle, it lifts the flapper, which allows the water to exit the tank and into the bowl. This is where the fill valve comes into play. A float attached to the fill valve sinks with the water level, which opens the fill valve to allow more water to enter the tank. When the tank fills, the float valve cuts off the water supply, leaving the toilet primed for the next flush. If your toilet no longer flushes properly or the tank doesn't fill, replace the toilet float valve to get things working again.

Things You'll Need

• Sponge
• Rags
• Pliers
• Plumber's tape

Instructions

1. Turn off the water supply for the toilet. The water supply valve is usually on the wall behind the toilet. Rotate this knob clockwise to turn off the water supply.

2. Flush the toilet to remove the water. You may need to do this more than once. Wipe up any remaining water with the rags and sponge.

3. Unscrew the water supply valve from the toilet float valve. This is at the bottom of the toilet tank. Turn the plastic coupling on the water supply hose counterclockwise to unscrew.

4. Loosen the plastic retaining nut just above where the water supply valve was connected.

5. Remove the float valve assembly from inside the toilet.

6. Replace the float valve assembly with the new one. Make sure the rubber gasket at the bottom of the valve assembly is firmly in contact with the bottom of the tank for a good seal. Hold this in place with your hand.

7. Thread on the lock nut for the fill assembly on the underside of the tank where the bottom of the assembly emerges from the tank, using your other hand. Tighten this hand-tight and then with an additional turn with the pliers.

8. Wrap the threads on the float valve assembly with plumber's tape. Thread the plastic end of the water supply hose to the inlet valve. Tighten with the pliers.

9. Restore the water supply by rotating the water supply valve counterclockwise. Allow the tank to fill.

10. Flush the toilet and check for proper operation.

Tips & Warnings

• When replacing the float valve, replace it with one that comes integrated with the float assembly. These are more efficient and work better than the older models with the ball float.

• If in doubt about any of these steps, consult a certified professional.

References

• Toiletology 101: Parts
• The Family Handyman: Replace Toilet Valves: Flappers, Fill Valves and Flush Valves