2005 Magnum A/C Problem

[kryten]

Hope that "General Discussions" can be used for techie questions...
The A/C in my 05 Magnum didn't seem to be as cold as it should be, in fact a bit luke warm. So I had it charged up with some 134a Freon.
A couple of weeks later, it didn't seem to work at all in some very hot weather we were having. In fact, the drivers side dash vents were blowing slightly cool air, but the passenger vents were blowing HOT air.
The A/C compressor is engaged, and the, small, high pressure line from the comp is very hot (which should be normal, right?). The larger return line is luke warm.
Anyone experience this? or have any suggestions?
Regards.