Silly but...... My A/C is too cold!

Does anyone understand the climate control system in these machines? I just got mine and am working hard to catch up.

Two Questions actually. Is the expansion valve a type where I can adjust it? My high side is running 275-300 with 1 pound 9oz R-134a. (1pound 12.4Oz is R134a ideal capacity)
PSI high should have been 176-200 on 80 degree F day.

The second Question is about climate control system. When adjusting the thermostat...... Does it control the clutch (cycles) or does it mix in warm air. My heater does not seem to work unless I am in "defroster effect" mode...... I have seen the diaphram valve actuate (and checked with MightyVac)

I experience headache cold (46F) cooling air from the center vent, I hear a relay cycle on/off and feel it in the accelerator. I turn the rheostat to heat (in celcius idunno the number) and get slightly warmer then vent air but not hot, with the compressor button off. With compressor button on and to heat I get a warmer 54F.

I hope that there way of adjusting the A/C temp is with a mixing valve, because I would hate the cycle cold to moderate to cold to moderate.... on a long trip. I dislike it now on a short trip.

gotta get to work........ Answer here to all my problems!

Kurt

The expansion valve (ptrc66.jpg) isn't adjustable. Wow that's some high pressure!

I'll dig through the shop manuals and get back to you on the rest.

I found the shop manual and am learning the system. I'm not looking forward to the steps necessary to actually getting to the unit. I am understanding that to get to the the actual servo motors and vaccuum solenoids I am going to have to remove most of the forward interior and the underhood blower assembly. Wish me luck!
Kurt