The reason why AC is running but not blowing air at all at any fan setting.
(1) Blown blower fuse.
(2) Failed blower motor.
Car troubleshooting
Blower not workingFirst off, we need to clear something up. The "blower" and the "fan" are the same things. We used the word "fan" in the problem description because it's a more familiar term. The official name for it (as used by mechanics) is "blower". Now then, it should be obvious that if the air isn't blowing from the vents at any fan/blower setting, the blower must not be working. Two common causes of this are:
Blown Fuse - Like most electrical devices, the blower has a fuse as part of its circuit. This fuse can "pop" for one reason or another. This will immediately cause the blower to stop working.
Failed Blower Motor - The blower motor is the heart of the blower and, as one might guess, it drives the blower wheel which in turn, blows air. Of course then, if the blower motor has failed, the blower won't work. Another possible, but rare, cause of an inoperative blower is a faulty dashboard fan/blower switch.
What to do?
First off, locate the car fuse box. Refer to the owner's manual if you aren't sure where it's located.
Once you've found the box, find the particular fuse that is associated with the blower (it should be labeled either "Heater" or "A/C"). Examine this fuse to see if it has blown. If so, replace it with a fuse that has an identical amperage rating (refer to owner's manual for this information). If the blower works but then fails again, there is likely a short circuit somewhere. You'll need professional assistance in this case.
If the fuse was intact, you likely have a failed blower motor or a problem with the switch's wiring, this will cause the AC not to blow air even though it is running. Take the car to a qualified mechanic for inspection and repair. Try to find a mechanic that specializes in A/C and heater repair. (See also Air Conditioner Not Blowing Cold Air but Running )