no hot water from tub/shower valve

the plumbing for this tub/shower is approx. 6 yrs old. it is a symmons model a temptrol located in a guest bath that is rarely used. when the knob is turned to cold, there is plenty of cold water, but when turned to hot, just a tricle of water comes out of either the tub spout or showerhead. i took out the adjustment screw and let some water out hoping that the problem was some lodged sediment, but it didnt help. i'm expecting guests this weekend and i'm hoping someone can help. thanks :confused:

Go to the Symmons web site and pull directions to disassemble this valve. It will most likely need to be disassembled and flushed. You could have a pressure balance spool that is sticking.
Deb
The Pipewench