Dang. I'm a renter, and the owner-landlord was difficult to work with last year when the same PTAC unit stopped blowing cold air on cool mode. Knowing the units are original 15+ years old, I suggested replacing them and he nearly blew up at me! I hardly ever contact him these days, and it's been months since we've communicated, aside from sending monthly rent checks.

So, last June, first tech came and recommended replacing compressor ($1000+), but second tech came and said all it needed was a new condenser coil ($100-$200), and that worked.