2002 Pontiac Ram Air Trans Am ac is not cooling properly

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Al9
Posts: 238
Joined: Tue Mar 10, 2020 3:26 am
Location: Southern Europe

Re: 2002 Pontiac Ram Air Trans Am ac is not cooling properly

Postby Al9 » Thu Dec 17, 2020 2:15 am

Whenever you're in doubt, a visit to an RRR station equipped pro is always money well spent, no matter how much.
When you turned the compressor on, it pulled refrigerant inside so slowly because, with so little refrigerant inside and so cold ambient temperature, it was fully destroked.

If it can be of consolation somewhat, i'm getting a steady (compressor is correctly regulating stroke at all rpms) 49F vent at 72F ambient with my new compressor and the new radiator fan, a new and externally clean condenser, a genuine (albeit second hand) factory TXV and the correct rating compressor control valve for my car. Not a heater core/box issue since it does the same with a cold engine. Charged in the summer with an RRR station, flushed system, every required oz of refrigerant and DEC PAG oil inside right before engaging the clutch for the first time. Double checked that everything was leak free because i got the control valve replaced to the correct one about 2 weeks later after having the compressor fitted so it again got serviced with an RRR station and the charge weight got evaluated. Either normal, or someone provided me with a valve whose rating is higher than what the color states. Vent temperature definitely felt colder (unless in very hot sunny days, when AC started acting up) right before i replaced the radiator fan (one cause for the AC issues i had), and right after replacing it, unfortunately, ambient never managed to climb up above 72F where i live, so i'll have to wait for next Spring.

In other words, wait for warmer weather to evaluate your system performance further. As i said earlier, the control valves used in both our compressors (yours and mine) have that little quirk of dropping vent temp as the high side pressure climbs up, and the opposite.
dannyual320
Posts: 47
Joined: Tue Aug 18, 2020 2:23 pm
Location: Montgomery, TX (just north of Houston)

Re: 2002 Pontiac Ram Air Trans Am ac is not cooling properly

Postby dannyual320 » Thu Dec 17, 2020 10:13 am

Thank you Al9 for your consoling words describing what is going on.

I was wondering if that variable displacement compressor was "destroking" since I never saw a high side pressure above 70 last night.

About a week ago, I told my father-in-law that . in the past, I've noticed that auto ac systems act differently in the cool weather vs the heat of the summer. I told him that I was a little apprehensive about doing this final reassembly, charging and testing while we're experiencing abnormally cold temperatures for the Houston area. On the other hand, I just wanted to get it done.

For now, I'm just going to give it a rest and like you, wait for warmer weather to do a proper test.

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