We have an R model with flight station and cargo a/c problems. The a/c is running full hot, no matter the setting. We have checked out the control box, and the temp control valve, both are working fine. When selected to hot, the temp control valve opens, when selcted to cold, it closes, so these are not the issues. I was wondering could it be 2 failed anit-ice valves? I was messing with the a/c anti-ice control panel with power on. The "open" lights both work. But, when I move the switch to the "open" position, the "open" light does not illuminate. Both gripes showed up a day apart. The aircraft was on det, and the flight station went out. The next day, cargo did the same. I need help!