Originally Posted by LiQuId
^ thats a grerat idea... this could well be the problem. I had never really thought that one would be restricted, but have never installed one in the upside down position if for nothing more than the fact of the arrow and the "this side up"
Me!! the only time I made a mistake was the day I thought I did. Just kidding.
I don't think I have but I have seen it done before. One other thing to remember about T&S valves never use PEX or CPVC on the tub spout. That will cause a restriction in that line that will force some water out the shower head when filling the tub.