85 Suburban A/C question

[SBTork]

A few nights ago I threw a charge of R12 in my 85 Burb after work, I work at a GM dealer that still has an R12 machine The suburban has rear air too and now it works awesome, but the front a/c does not blow cold. I also put dye in it and plan on checking for leaks, but I am not convinced that's the issue. The compressor kicks on and off just fine and has no obvious problems. Has anyone had this problem and found a solution, or know of one? I am thinking maybe I just don't have enough refrigerant in the system, possibly a switch or something but I am not well schooled on a/c.

Any ideas or suggestions?

[RandyP]

They share the freon from front to back, so that should not be your issue. I've never taken a burb with rear A/C apart to be sure what is back there, but I always thought they shared the compressor and all that was in the back is a blower and evaporator core at most.

Does it do anything in the front when you slide the cold/hot lever? If there is never any temp change when moving that, even on Vent or defrost, I'd say that is your problem and start chasing those components to find the fault.

I'm really like you though, I am not an A/C guy beyond hooking up the low and high lines and doing what the A/C machine tells me to do.

[SBTork]

thanks for the reply Randy, when the temp lever is moved the temp of the air coming out of the ducts also changes accordingly, just not cold as indicated

[RandyP]

Just sit in the back and get the little lady to drive?

If nothing else I'll ask my tech Monday morning what he knows about them. I'm not certain if the rear has separate high pressure sensors and what not. So it will not blow cold no matter where you have it set, even on defrost right? On defrost (even in winter when you have it on hot/warm) it kicks in the A/C system so it blows dry air.

[SBTork]

Thank you Randy, you got me thinking, I think I may have an idea....

In november, when I bought the suburban, I put a heater core in it and parked it for the winter. I remember asjusting where the temp cable bolts to the heater box to make sure I was getting heat. It's possible that when I adjusted it I was more concerned about hot then cold and adjusted it too far one way. Possibly......I will update once checked.