Fill Valves
Products > Fill Valves
400A - Universal Fill Valve

- The original 400A was first introduced in 1975
- The #1 selling fill valve in the world
- The #1 solution to fix noisy toilets
- Easy to install, Universal fit
- EZ-Twist height adjusts from 9″ to 14″ to fit most toilets
- Trusted by toilet manufacturers and plumbers worldwide
- 5 year warranty
For best performance of your toilet, consider replacing the flapper along with the fill valve. Fluidmaster recommends the 400CR Repair Kit that has both the 400A fill valve as well as the 2 inch 501 flapper.
Watch this video on how to install the Fluidmaster 400A Fill Valve:
If your fill valve runs continuously or you hear a constant hissing sound, you may have debris trapped in the valve. This video will show you how to properly remove debris from the 400A fill valve:
If removing the debris from the 400A fill valve did not solve your problem, then the next step would be to remove and replace the cap assembly of the 400A fill valve. This video will show you how to remove & replace the cap assembly:
If you are wondering what is the difference between the 400A and the 400AH PerforMAX® fill valve, we have just the right video for you:
To check your toilet’s flush volume, please click here.
Frequently Asked Questions
-
What toilets will the 400A work with?
-
How do I raise the water level inside the tank after I installed the 400A?
-
Why does my 400A keep turning on and off throughout the day & night?
-
Are there any repair parts available for my 400A?
-
Will the 400A work with my flapper?
-
How can I tell if the 400A will work in my toilet?
-
Can I use a filter with my 400A?
-
How can I get a replacement under the warranty?

Cancer and Reproductive Harm - www.P65Warnings.ca.gov.