I have a few problems with the A/C in my 2002 KIA Spectra.
 1) In order to turn on the a/c, you have play around with the fan and fresh/recirc buttons.  Usually, fan on low and fresh air will work.  Then when you press the a/c button it will turn green and you her the condenser kick in.  Otherwise, nothing happens.
 2) Last summer the a/c was a little weak, this year it is very weak.  I saw a recharge kit w/leak stop at the parts store for $50.  If it is not too difficult, I will give it a try.  I never did any a/c work.
 3) The blower seems to be not as strong as it used to be.  It used to force 1 vent to shut, so I wedged a piece of paper to keep it open.  Now, paper not needed.  Also, the passenger side is noticeably weaker.  I pulled out the blow and small hose.  Cleaned up some debris but that didn’t seem to make a difference.
 Thanks for any advice.
The only suggestion I can make is to take it to a shop that does automotive AC work.
Sorry.