Air conditioning DIY, need advice

I have a 96 aurora that needs the AC charged. Is there a valve on the low side of the system? If not is it possible to charge it on the high pressure side with the little cans of r134? The other thing that really has me wondering is the 2 valves on the top side of what appears to be the high pressure line. Whats the logic in that? This system has me very confused. Can anyone shed some light on how this thing works?

Thanks in advance!

The line you see is actually a high/low pressure line. Between the 2 fittings you will see where the line comes apart. In there is the orfice tube where the high pressure liquid is changed to low pressure gas. The low pressure (smaller ) fitting is the one more towards the firewall.

Smingee67....Charge the system through the low
pressure side. The system pressure there is appx.
30 lbs. The 134a in the can has a pressure of about
75 lbs., so that will override the system pressure
and allow the 134a to be drawn into the system.
The A/C has to be on to allow recharging.


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GM!!! BRING BACK OLDS!!!

Thanks tons! Thats exactly what I needed to know. :thumbsup:

Smingee67,If you are able to do it.Please let me know,how you did that.
I brought a service kit from wal-mart for the same reason,but the coupler does not fit on the low pressure end.Am I doing any thing wrong?

I've read that the kit with the plastic fitting doesnt work so good and one with a metal fitting does. Either way my father-in-law has several types of fittings and adapters to choose from so I'm hoping when the time comes I'll have something that works.
If I make some progress I'll be sure to post it :)

Well I added a can of oil to the system since there was no pressure in the system at all and tried to see if the compressor would kick on. Sadly it didnt. I even added a can of R134 to it to get the pressure up hoping something would happen but no luck. Seems the problem is more serious than I thought. I used a fill kit with a Pressure gauge on it that had a plastic fitting and it worked just fine. The system was reading about 35psi so I will check to see if its even holding pressure at all after work tonight.