only warm water in shower please help!!!

[danielspack]

ok so...
we put in a new shower and now the water doesn't get hot, even though it's super hot in the sink that's off the same line, only four feet away?
we replaced the valves, and cartridges, still nothing.
then even turned off the cold water completely so that only hot could come through, and that didn't even work?
i have no idea what to try next please help!!!!!!

[GoldMaple]

This is Too Funny! I had the same problem on my basement bathroom project. I had to redo all the plumbing in the bathroom so I pulled it all out and then put all new piping in. The upstairs bathtub/shower lines were in this basement bathroom so I did them, too. I finished at 2 in the morning.... Did a test and all was good. Next morning my wife has a shower upstairs and says, "there's a problem in the shower. It only gets warm!" Crap! Did I cross a line? Nope, all good. WTF...... I damn near started ripping the pipe out! Part of my project was to add shut off valves to all the fixtures. So, I shut off the basement shower stall and suddenly the upstairs shower/bathtub has very hot or very cold water. I then realized that the shower rough in only has a test cap on it so the hot and cold water are mixing through the rough in!!!! Everything is cool.......just put the shower valve in.

[danielspack]

i didn't actually add another shower though.
just changed the old one.
i thought it might have been something with the shut off valves but nothing gets hot even when i turn off the cold water completely?
this is soooooo frustrating.
thanks for the quick response!

[jadnashua]

New anti-scald shower valves have two things: the ability to automatically adjust if the pressure drops on one side verses the other keeping the balance approximately the same (same temp), AND an upper limit adjustment. You may need to adjust that upper limit. Depending on the model, that could be a screw, or a lever, or a clip that is generally accessable only when the trim is removed. Note, if your water temp changes radically (the cold side) between winter and summer, if you set it in winter when the incoming cold is frigid, you may get too hot of an output in the summer when the cold is (potentially much) warmer.

Another possibility is there is some crud in the valve that is blocking flow slightly, preventing the hot from flowing freely.