AC repair - Not sure what's going on with pressures

System takes 19oz, I have put 19oz equivalent of a hydrocarbon alternative called R12A. Before you're quick to say it's the refrigerant, it's very likely not. I have used it before in the past and I did not run into these sorts of issues.

I am only using it because it's what's commonly available here, I have R134A but don't want to waste it nor do I want to be releasing it into the atmosphere trying to diagnose my issues. I plan on putting R134A once I've traced the leak and replaced the necessary parts. In my experience, the lowside pressures are very similar to R134A while the high side pressures are maybe 20PSI lower.

Is there an issue with the way I'm charging perhaps? I have the system fully vacuumed down to -26in/Hg before the pump is disconnected and the refrigerant is charged(Yes, I'm also purging my lines properly). Is the refrigerant suppose to be charged into the system while the entire system is under vacuum?

/r/MechanicAdvice Thread Parent