it might not be a matter of it losing it so to speak, freon can turn to a gas known as SO2 which will dissipate, it depends on how fast it is being lost. most cars require AC to be recharged from time to time, you can do this yourself. They no longer sell Freon, but they sell a "R-134a" recharge kit, which is a safe alternative to freon. SO2 is a very deadly and explosive gas, as well as freon being bad for the environment as a whole.
Compresser is out of freon. Needs a re charge. Or compressor blown
i would first start by checking the amount of freon the a/c compresser has, it would also be a good idea to flush and refill fill it since you've already gone this far.
Does a tire with a slow leak lose air when you are driving in reverse?
if you've still have freon its old! and you must retrieve the old stuff before you put in the new! I think you can get to much in and freeze up. or your compresser is out!
Simplest answer is that the refrigerant (freon) may have leaked out. Also could be: loose wire - faulty A/C relay or fuse - bad compresser - you need to have it looked at and the possibilities narrowed down.
Yes
Air Compresser
Freon mixed with refrigerate oil will have a slight smell.................
you would need to add freon
It will probably get noisy and leak oil and freon. If you wait for it to seize it will be more costly to repair because it will fill the system with metal that must be cleaned out before a new compressor is installed.
Compressed air production.
Adding freon to an air conditioning unit should only be done by a certified technician. It is in fact illegal for anyone to add freon to air conditioning that isn't properly certified, so one would add freon by calling in a certified technician to do it for them.