I had a plumber install a shower/ spa it is a moentrol and all I can get is hot water and I have pulled the shower apart and checked the spool it was clear and I checked the cartriges and I screwed the two screws on each side of the spool all the way out and half way in and it would change the temperature one way or the other but it was eathier hot or cold no happy medium. The cartridge looked good. Does any body think the balancing spool could be messed up or any [email protected]