… It's not a difficult task to unscrew the back and pop the battery cover off, and the battery itself is plug & play as long as AA is willing to send you a new one...
True, but I understood that opening it yourself it voids the warranty??? I have no trepidation replacing a battery myself if AA would send me one, but I would have the factory do it rather than a dealer so the whole unit gets thoroughly checked out. There are no AA dealers within two hours of me anyway.
… Might want to check/clean the overpressure ball valve while you're in there.
Ball valve? Do you mean relief valve?