Jeep Repair: 1994 Jeep Grand Cherokee A/C problems, jeep grand cherokee, vacuum tube

Question
Hello. I recently became the new owner of a 1994 Jeep Grand Cherokee. My sister gave it to me because she didn't want to deal with its many "quirks" any longer.  I have fixed most of them, but saved the biggest and most important problem for last.  I live in Florida and the A/C doesn't work! I know this is kind of a broad topic, but the ATC system does not blow cold air regardless of what temperature the system is set to. I have already checked to make sure the problem isn't the compressor or freon level or anything like that.  Someone suggested it may be a hot/cold valve under the dash that needs to be replaced (to the tune of $400). Have you ever heard of this?  Do you have any knowledge or thoughts concerning the problem? Anything would be greatly appreciated. Thanks for your time.

Hesper


Answer
Before investing in someone tearing apart the heater box under the dash and fixing the diverter door, I would have the heater controls checked out.  You might have a wire or vacuum tube broken and that is a lot easier and cheaper to fix than what you are looking at.