Yeah, now that you say that, I have no idea. Since the outside temp was 95° and the inside wouldn't get below 75°, I'm guessing that differential. Obviously, the evaporator gets much cooler than that, so I guess it's a sizing issue.

I don't know how hot the compressed refrigerant gets, but I'm guessing no more than 175°, so a difference between 85° and 95° in its heat sink (the surrounding air) is probably reasonably significant.