I have scaulding hot water in every faucet of my house, but as of last night my shower does not! I have to turn the water control in my shower all the way to hot just to take a mildy warm shower. I checked the shut off for the hot water to that bathroom and that is not a factor. My father and father in law say it could possibly be a bad or clogged mixer valve. Any ideas and possible fixes would be greatly appreciated.

