I have 2 showers 1 with temp control the other doesn't.when I run the sinks the water comes out hot. I ran the hot water for the shower and check he pipe it was warm then ran the sinks the pipe was hot. I have a oil furnace that heats the hot water.

I think your mixing valve is partially plugged up on the hot side. Do you know how to disassemble and clean the mixer? If not just post back here and someone will help you.

I think your shower valve has a high limit anti-scald quard. It may need to be adjusted. What brand do you have?