I should also have mentioned the cabin air filter has been maintained. Excellent. I found the following on the internet, regarding a "rough test of the AC system would be to turn the fan on low, set the temp at minimum, set the vent to fresh air, run the engine rpm at around 2500. Measure the ...

Generally, seasonal refrigerant losses will occur over time, usually from seepage through the compressor-shaft seal. My main concern is operating an MVAC system with a lower-than-optimal refrigerant charge, which will cause the compressor to run with less oil, risking internal damage or even complet...

On this Forum, we don't advocate the use of non-EPA-approved refrigerants. See "Forum rules," Item #3. So I'm afraid we can't help you with that question. Please DO post again with any additional questions you might have.

Rweaver428 wrote: ↑Sat Apr 20, 2024 7:42 am I will gladly scan the Clardy docs and attach them if it would help someone.

I'm curious about the original R-12 spec...I would guess about 3 pounds.

From outward appearances, your original TXV looks pretty good. Hopefully, the internal sealed and charged portion is intact as well. The refrigerant doesn't "matter" to a TXV. I believe there is sophisticated equipment that not many people have to verify a TXV's operation. Best option for ...

I have the original installation instructions, charging instructions, and parts diagram. That's "gold." Be sure to hang onto it. I would like to replace the original expansion valve with a new one, but I’m not sure which one to get. Unless the original TXV is corroded or otherwise damaged...

I forgot to mention the specs that I have for your car: 16 ounces net weight of R-134a, and 4.4 fluid ounces of PAG-46 oil. However, if your car still has its under-hood A/C decal, go by those specs instead because the decal takes precedence.

A reading on the low side of 21 PSI at 1,500 RPM translates to an evaporator temperature (coincidently) of about 21°F, which will cause the evaporator to freeze-up and block airflow through the vents under certain conditions. It's also an indication that the system is undercharged. The Schrader valv...

I agree with the preceding comments. It appears to be low on refrigerant. Have the refrigerant recovered, then the system evacuated and recharged to specs, adding back the proper amount and type of oil if any was recovered along with the refrigerant. The ambient temperature is a bit low for MVAC wor...

The system is bumping into the High Pressure Cut-Off (HPCO). A few issues can cause that. Foremost is a blocked Orifice Tube (OT) that can prevent circulation of the refrigerant and oil and cause extremely high pressure to build up on the high side, which you noticed. The OT itself is inexpensive. H...