Ok so for some reason when I was in trade school they never taught me how to get the subcooling and superheat. They only taught us how weigh it in... I know you gotta get the high side pressure and convert it to temp, and get the temp of the liquid line with a clamp on thermometer and subtract the two. But this hvac buddy app wants the ambient temp outside and the wetbulb temp at the return. Can someone explain please? Do I need those air temps to get subcool???