I had a blown O-ring at my AC condencer which I repaced yesterday, the system had been uncharged for nearly 3 years. I believe that was the only leak I had. The problem is the shops I have called want $30 just to pull a vaccum and tell me if there are any other leaks :bsflag:. So my new plan is to buy a retrofit kit and charge the system with 134a and record the pressures. Tomarrow I'll check the pressures again and see where I am at. Barring any leaks I will then vent the system, replace my dryer, and charge it with the ES-12a. Does this sound rational and is there anything else that I need/should do?