Here is a page that looks at fill valves
We just replaced the our Toto Toilet Fill Valve. We got the right one after calling Toto. I was also told they are universal. After putting the new valve on and adjusting the fill #'s to what the other valve was marked at.
(we could not find the model # anywhere. Was not inside the tank as they said it should be so we went by the old valve) The toilet is filling continuously by itself. Can anyone tell me what we need to do. We put the valve height at the lowest number. We could not find where to adjust the refill ratio key setting. It would also help if anyone knows where the model # might be?
The Toto universal fill valve TSU99A.X is made by Korky and is very similar to the Korky 528MP valve, except that it comes with some stuff that allows you to adjust it very, very precisely to exactly match the tank level and refill ratio that Toto designed into the toilet -- assuming that you know the model number of the toilet.
You can do a couple of things: First, you can post a low-resolution photo here of your toilet, as well as a picture of the inside of the tank and we can probably tell you what it is. Then you can pull out the instructions that came with the valve and set it according to those instructions.
Second, you have an alternative. There is more than one way to skin a cat (and to know how to set the fill valve). Here are the instructions that Korky provides for its 528MP fill valve. CLICK HERE FOR LINK TO INSTRUCTIONS
Also, here is a video from Korky on how to install the 528MP and set the height and refill ratio.
This shows you how to set the refill ratio without using the precise Toto key. (What you do is adjust the refill water until the thing fills just finishes filling the bowl to the proper level before the valve shuts off as a result of the tank being full. You determine the proper bowl fill level by opening the refill adjuster all the way and essentially overfilling the bowl a bit, then you let the water settle for 2 minutes; all toilets have a natural level to which the water settles and above which any refilling will simply run down the drain.)
In terms of how high to set the water in the tank, most Totos have some writing inside that says something to the effect of set the water level 1/2" below the top of the overflow riser. See if yours has that and what it says, then set the valve to achieve that level in the tank.
As far as it running, here's a video on how to troubleshoot the valve: LINK TO VIDEO
Last edited by wjcandee; 11-14-2012 at 06:17 PM.