Rear A/c on 1998 GMC Savana 1500

I got a 98 gmc Savana 1500 auto form conversion van. It runs really good have had some minor problems with it and have been able to take take care of the problems all on my own except 1. The rear A/C does not work on this van. The only thing that comes out is hot air. Its just hard to believe that this was once a 35k van without rear a/c. is there something that controls the rear a/c to turn on or is there only a heater.

3 answers 1 comment
I had the same problem. The answer is to check your fuses. Mine was blown. Simple and easy problem. Rear ac works fine now.
Which fuses? I checked the ones in the cab on the driverside. Is it a fuse under the hood?
We are having the exact same problem! Have you found any answers yet???
There is a set of valves that control heat and ac to the back. I had it repaired at local shop. The mac said the valve was bad that shut the heat off to the rear ac. Replaced the valves good cold air to the rear now.