Originally Posted by accordvtec77
when the A/C system is exposed to the atmosphere (opening lines for example), it HAS to be hooked up to an A/C machine that can "vacuum" the system out before you add any freon, otherwise you can add all the freon in existence and it still won't blow cold.
i know that, because if you were to open a line while there is freon in it, it will naturally go into the atmosphere which costs quite a bit of money if someone reports it. I meant like vaccum'n out the system and seeing if it would hold a vaccum otherwise it might have a leak. I haven't really fixed a lot of ac's yet so i'm not real sure on this stuff yet.
I start classes for my auto mechanics degree next month...so maybe after a year or two i'll know better ways to answer these. sorry if that sounded retardted.