I would get the Illustrated Parts Breakdown for your unit and look it over for possible internal leaks. If the unit hasn't been maintained or serviced on a regular basis the internal seals & "O" rings dry out, get hard & develop cracks, which are small at first, but eventually blow out. You may just need to replace the Packing Kit or seals & "O" rings. Since you have a pen camera you may want to look for small cracks in joints, welds and "O" ring seats. It sounds like the carcass is good, no pin hole leaks or distortions. If you feel confident about tearing it apart and changing the seals & "O" rings then go for it. You could also get a certified A/C repairman to do the job. They have the special tools and are familiar with the problems that certian A/C units commonly have. Also, if you end up doing it yourself don't forget to lube, or condition, the seals & "O" rings before you put them in. I used a light coating of silicone de-electric grease worked between my fingers. I wiped off the excess on the rings after they were on. The grease helps keep the rubber supple. Adds a little bit of life to the ring. Good Luck!!
