speaking from a guy who does a/c work , it probably needs freon . Now you don't have any place to add the freon , so you have to take it in , and they add a port to add thru. Here's the kicker though , after time the lil clamp on they add, to add the freon will leak and you'll be back in the same boat . alternative .. they braze a port on , trouble is this is very expensive .. you figure out what you want to do . I'd go get a quote on adding both ways
Nort73, February 2010