Let's face it: when it's 95 degrees and humid outside, and you've been stuck in the car for six hours with three rowdy kids, one slobbering canine and a grouchy in-law, having working AC might just be the only thing that keeps you from diving out the window and running headlong into the grille of an oncoming Mac truck.
There's nothing to really maintain, per se, on your air conditioning system, but there are a few important things that are worth checking. Here’s why it matters: Failing AC can affect more than just the cool breeze blowing in your face. On most modern cars, the serpentine belt that helps power the air conditioner also provides power to other things, too—including the water pump that keeps your engine from overheating, for example. If your AC fails, your summer safari could come to a screeching halt faster than you can say, "Pass the Right Guard!"
First, check to see that you're getting some cold air coming out of the vents when you turn on your AC. Next, consider asking your mechanic to check to make sure that the AC system is fully charged with refrigerant. Finally, ask your mechanic to check for a noisy compressor, and to listen for the telltale sounds of a noisy or worn AC clutch. -- The Car Guys