A.C. Compressor - 2 quick questions...?

[svxcess95]

Hello All,

I hit the wall with something and wanted to see if anyone here had some info that could help me out. I went to go recharge my refrigerant this weekend. I hooked it up to the low side and filled up. After filling, I heard / noticed I had a small leak (I heard a hissing noise and saw condensation forming) right where the high side of the loop comes back into the compressor. Is there an "o-ring" at this location that could have gone bad? I didn't want to unscrew the high side before I knew for sure because I wasn't sure if the system is under pressure and if it is, how to repressurize it. Any thoughts?