Toilets, Sinks, Showers, Tubs and Disposals - Shower water not hot enough

All other faucets in house have hot water to enjoy, but for showers it does not get hot enough. We have turned temp up on water heater, but, that does not seem to help. I am assuming it is a temp. controlled faucet in both our bathrooms. So how do we adjust or take that out? Driving us crazy! :thinker:

Turn the water heater back down to normal heat. Then, remove the handle of the shower, either via a set screw or regular screw in the middle. Under it you will see a white nylon disk. Note its position. When you remove it, you will note it is splined on the inside, while the place you pulled it from is splined on the outside. From its original position, move it about 4 splines counterclockwise, push it back on and replace the handle temporarily. Try the shower to see if it gets hotter. If not to your satisfaction, move it more to the counterclockwise position until you get it right.