: My name is gary. One of my tile customers has a problem with her shower in which the cold water works fine but put it on hot and the water barely comes out. I put in a new cartridge for her thinking maybe it was just old, but the same thing is still happening. Does she need to have a plumber come and change the pipes or could there be another explanation?

: Thanks for your help.

If this is a Moentrol, there is a balance spool that could be affecting things. The cartridge itself is a simple thing (but it doesn't do most of the work;-).
If there is no balance spool and all the other hots are working fine, you probably need a plumber...
Deb
The Pipewench