Hello,
I've been working to revive the A/C in my '66 Toronado. I rebuilt the A6 compressor, had the hoses remade, replaced all o-rings, dryer, flushed the system, added 10 oz of PAG oil150 and 30oz of R152a (manual called for 4 lbs of R12, so 60% of that).

I had tested the POA with compressed air and set it to 30 PSI. With the system running, it still read 30 PSI. High side was 80 PSI. The hose coming out of the evaporator was cool, but after the POA, it became very cold, to the point that frost was forming on it. Outlet air temperature was probably in the 50s (60deg day).

Any suggestions?

Thanks.

 

The POA is clogged or restricted .
Did you pull a good vacuum of 30 inches or more for at least two hours , before charging ?
Also the POA may need a different setting for R-152 .
You might try consulting with Original air group ;
https://www.originalair.com/FitmentC.../FitmentSearch

 

It held a vacuum for 1/2 hour before I charged it.

That the POA seems to be acting as an expansion valve would seem to confirm that it's restricting flow, but would a clogged POA still be able to regulate pressure?

Thanks.

 

You are 8 ounces short on refrigerant based on the information you posted.

 

No , it acts like an expansion valve .
Re-build or replace the POA . Making sure it is adjusted to R-152 standards , if that is what you are using .

 

I have another POA valve. I'll switch it tomorrow. Thanks.

 

Question - what is R-152?

 

It's an industrial refrigerant that is commonly used in keyboard duster sprays. It's supposed to have very similar properties to R12 and work very well in unmodified R12 systems. And it's dirt cheap.