AC blowing hot? Hopefully it's JUST the control panel! Does the compressor engage without any abnormal noises? If so, check the hoses behind the dashboard that have a tendency to disintegrate. If the compressor is making strange noises, you'll need to replace it, the receiver dryer and expansion valve too. Look to spend around $400 on parts, and $700 on labor. I know, I was planning to do the same repair to my previous car.