Air Conditioning Forum

[DUMPTUBE]

I know now is not the appropriate time of year. However, we run an auto Airconditioning shop, and would be happy to help with any questions or problems fellow TB members are having.........just a thought.

P.S. We have been doing auto airconditioning for over 15 years now......that's all we do, so I think there could be some benefit.

Thanks for reading.

Brett Anderson

[norb]

Thinking about this in my car, can't find r12, and 134a just sucks, tried everything with it.

http://www.duracool.com/faq.html

[DUMPTUBE]

Norb.............
There are a lot of mis-conceptios about R134A. If done properly, it will work just as good as R-12. I did not view the link you supplied, as I would highly recommend not putting anything in your car other than R-12, or R-134A.

If you notice, most all of the newer vehicles are coming out with two condensor/radiator fans, and have what is called a parallel flow type condesor. These two combined create a greater and more efficient condensor flow, and allow for the R134A to work extremely well.

Not to turn this into a selling reply, but I do have some virgin cans or R-12 available. However, if your car is converted to 134A properly, it should and will work fine. What area of the country are you in? Do you have a front mount intercooler?

Again, not trying to sell you anything, but we do stock parallel flow condensors that will work on any GN, and by using one of those, you won't have any problems cooling your car.

I hope this helps, and again, I would not, would not recommend putting any of those blends in your car.

Brett Anderson

[norb]

Bret,

Yes i have a front mount intercooler, i have two electric fans that flow 4000 cfm, and draw 52 amps. The dryer is new, the compressor is brand new. The system blows cold air when the car is cool, let it sit in the sun with the engine hot, and it will take 30 minutes to cool the car inside. WHen the car had r-12 it would cool the car in easily, with the stock electric fans. at idle the high pressure is around 250-260 and the low pressure about 30 on a 77 degree day. Oultet temps when the car is cold, but hot outside are 52 degreess, this goes up to 61 degrees idling in traffic, based on a 85 degree day. This is center vent fan hi MAX closed windows. MY a/c guy says since the high pressure is so high i can't get better cooling. The system has as i recall 2 3/4 lbs of 134a in it. I think i contacted you last year, and you said there is no direct fit parrallel flow condensor that bolts in a gn without extensive mods to orginall fittings and lines. Bring r-12 or selling r-12 across the border is worse than selling drugs, some crazy fine/imprisonment etc.

I am into Toronto, not that hot but we have very humid air.

[DUMPTUBE]

I know what you mean about selling R-12. You have to be licensed to buy it, not that you can really get it anymore. We are putting together a parallel flow condensor kit, to go on the turbo buick. It is currently in the works, and will end up being a bolt-on set-up. These condensors are really neat, and work great. I will keep you posted on the progress of the project.

Your pressures should be checked at about 1800 rpm's. What rpm are you getting those pressures at? The testing for your pressures should be close to those of what you would do in normal day driving. If the system is working properly, it will provide maximum cooling under 2000 rpm's.

You stated you are running 260 psi of discharge pressure on a 77 degree day, which would put it well over 300 on a 90 degree day, which is well out of specs. Hypothetically, if the proper charge for R-12 is 2.75 pounds, you need to multiply that weight by 80% to get the proper charge for 134A. Doing so would mean that 2.2 pounds is the proper charge with 134A. I will double check this weekend and make sure for you. If your R-12 condenser is not efficient enough, the vehicle will not cool with this charge.

The new parallel flow condensors that we are installing will reduce the head pressure by approximately 40%, which should increase your cooling capacity by that same percentage. In other words, you should be able to get temps in the low 40's from the vents in the car, on a hot day. We have done this thousands of times, and it works well on early model vehicles such as our Grand Nationals.

Thanks again,
Brett Anderson

[norb]

I'd go for the condensor if you can make it an easy install. Those pressures were at about 1000 rpm idle, im sure the high pressure would go down if i reved it up to 1800 rpm. I will standby when you have the kit ready to go. The buick system is rated 3.25 lbs of r-12

Thanks norb

[DUMPTUBE]

I sent you back a PM on the tb site. Let me know what you think, and if you want, I'll start fabricating it this week, and will be able to get one out to you pretty soon.

thanks,
brett :applaus:

[SuperSix]

I sent you back a PM on the tb site. Let me know what you think, and if you want, I'll start fabricating it this week, and will be able to get one out to you pretty soon.

thanks,
brett :applaus:

I agree - A/C is a tough task to handle on any car, and would like to see a forum for it. Maybe Jim Testa can moderate? He's helped me immensely in the past..

I bought a case of R12 on EBay a few years ago - my cars are still R12. My biggest A/C project was on my current driver, the 87 T. Compressor was frozen up when I got it.. Replaced the compressor, blew out the lines, recharged - been great for almost a year now. :D

[DUMPTUBE]

You seem to have a pretty good hold on the workings of the A/C system. I followed your posts on the pressures vs. low fan speed thread. The pressure switch is simply there to cycle the compressor off, when the pressure in the A/C lines gets too high. This helps to keep it from locking up.

The R4 compressor tends to fail somewhat frequently. We replace quite a few of them on many different vehicles, especially 88-95 GM pickups. Moreover, they are somewhat noisy......even when new.

Brett

[SuperSix]

You seem to have a pretty good hold on the workings of the A/C system. I followed your posts on the pressures vs. low fan speed thread. The pressure switch is simply there to cycle the compressor off, when the pressure in the A/C lines gets too high. This helps to keep it from locking up.

The R4 compressor tends to fail somewhat frequently. We replace quite a few of them on many different vehicles, especially 88-95 GM pickups. Moreover, they are somewhat noisy......even when new.

Brett


Bugging the crap outta Jim Testa, and using the info on GNTType.org helps. :)

I live in Tampa Florida - and since this car is my daily driver- A/C is mandatory. :D

[DUMPTUBE]

Yeah....our A/C shop is in Savannah, GA. We do about 75% of our business in about 5-6 months. The humidity in the South is killer. Good luck down there in Tampa, and if there is anything I can do to help you, let me know.

Brett