Thanks for all of the great info guys! This Texas summer is getting worse so this is what we have found so far........
yep, the vacuum doesn't control if it blows hot or not, today when we got home he told me that at one point when he stopped the a/c clutch wasnt engaged and the compressor wasn't running. I told him about all of y'alls wonderful ideas and we pulled the connector for the low pressure switch and used some stuff we use in the electronics industry called deoxit which is used to clean electric connectors. So far so good, I took it down the road and it never stopped blowing cold air once in the 45 minute drive.
will keep you posted at to if it comes back or not.