A/C stopped working CGT - need advice

[J. Lyons]

Hello all,

Well summer heat is upon us here in the East Bay Area. So I go to fire
up the A/C in my CGT turbo the other day (have not used it in 8-9
months) only  to find it no longer blows cold. WONDERFUL!

Anyhow, it seems that the compressor clutch is engaging (can here it
click on) but no cold air comes out of my vents. I was under the
impression that if the system was not pressurized that the compressor
clutch would not engage (at least that's how it seemed to work on my '79
5KS) since it used the freon as the pump lubricant, so I believe the
system is still charged. Am I correct in my thinking here?

I have checked the heater valve (it is not stuck open), and the vacuum
line to the fresh air intake (had the check valve go bad once, resulted
in similar A/C problem) but it is not that either. All other HVAC
features are functioning properly.

Any ideas guys? I've seen a lot of posts recently about A/C problems (so
it must be that time of year), so maybe somebody has the answer for me too.

TIA
J. Lyons
84 CGT turbo
86 4KCSQ
79 5KS