Just my 2 cents.

If you have/had a leak and the system sat idle for 7 mons., you may be out of refrigerant. Some cars have a low pressure switch on the receiver-dryer. If you'relow enough on refrigerant, the clutch will not engage and drive the compressor. There could be MANY other things as well. Consider having a pro look at it.

Mike Murrell
'91 300-SEL
Boerne Texas