Are you glad that you bring up the question? I do not want the system blow up in front of your face when you charging it from the high side. It is a very high pressure system - high enough that can kill you when things go wrong.
I heard the news last year that a group of students having a BBQ party of some kind. One student threw an unopen can (beer?) into the fire and it explosed killing one of his friends. I, at one time, tried to unmount a 14 inch tire from a wheel. After I put the tire on a tire machine, I should deflate it by removing the valve. I did not do that but tried to cut the rubber slightly to deflate it. It was only 30 psi pressure but I underestimated the power of air pressure. It exploded. Thing happened so quickly that I did not hear the noise of explosion but I felt my face was wet (due to the water inside the tire). My hair got wet also and went straight up. My hand was numb. The knife flew away. One of my pockets on my coverall flew away too. One of my sleeve came off the coverall. I lost 90% of hearing both ears the first hour, 50% hearing at the end of the day. It took two weeks to get all my hearing back.
You possibly had fun reading my story but it was a good lesson for me. Otherwise, next time I may not be that luck. There is always a danger of A/C hose rupture. Wear protective glasses when work on the A/C under the hood. Improper usage of the charging equipements is very dangerous. Learn enough about it before you start.
[This message has been edited by be459 (edited 05-13-2000).]