2006 Saturn Ion

Air Conditioning problem
2006 Saturn Ion 4 cyl Front Wheel Drive Automatic 30,000 miles

Last summer my AC worked fine, I decided that I wanted to add refrigerant to it to make it cooler since it was too hot in my hometown. My brother in law put the whole bottle of refrigerant in to it when I turned the car on the air started to come out HOT! It doesn't come out hot anylonge, it comes out warm.
I had a mechanic look at it today and he said that is either the compressor or that it needs refrigerant, is this true?
Thank you very much!
June 10, 2010.

Check the high and low pressure with a manifold gauge to determine the amount of freon in it, if okay also check if the magnetic clutch is engaging the compressor when you turn on the AC.

Jun 11, 2010.