Stupid AC question .... Is it r-12 or 134A

If you do indeed have the old style AC system (I am not a 348 owner, thus I'm not sure exactly what you mean) setup to use R12 ("Freon") refrigerant and the previous owner filled the system with R134a, then you may have a problem. I'm not an HVAC specialist by any stretch of the imagination, but it is my understanding that the AC systems using compressors, evaporators, dryers, etc.. setup for R12 need to be "converted" to use R134a - requiring flushing of the AC hoses, a change of sealing rings, gaskets, dryer, etc. -not just a simple re-charge with the newer R134a refrigerant. As I remember it, the new, environmentally more friendly (you have to love the "Greenies") R134a is more "corrosive" than the older R12 refrigerant, thus necessitating the retrofit. Given the situation, I would take it to an AC shop and have them check-out the system completely. If it is an older system you may have to convert to R134a, although it is still possible to find shops/HVAC techs that still have a "store" of R12 "in the back". However, it is supposed to be illegal to fill car systems with R12 now. If R134a was used and it did cause damage to your system, then it might be quite expensive. If actually required, don't buy an OEM Ferrari compressor, buy one from Ricambi - which is the same Sanden compressor that Ferrari uses at 1/4 the price. Also, www.vintageair.com sells many types of AC components. Good luck and I hope this post has been somewhat helpful.

P.S. Most Ferrari AC units really prior to the F430 don't really have great cooling capacity. You should feel the AC in the 1970s and 1980-1982 308 GTXi cars - forget it!!! They got progressively better with each model.

 

Being a 94 model I am pretty sure it should have R134A in there mate.

But take it to an a/c specialist and they will be able to put some a/c gauges on it to see what your a/c pressures are doing.

That will help them diagnose what is wrong with your a/c brother.

 

Pap, being an actual 348 owner and VERY experienced, is most certainly much more of an expert then I am. I, too, was rather surprised that you thought a car from the 1990s would have an AC system charged with R12 refrigerant. I've only heard this type of R12/R134a problem in the older 1980-1982 308 GTXi series cars that used the old "box-style" York AC compressors, rather than the rotary cylinder Sanden models. These old units, if the owner wanted to keep them, required retro-fitting to use the R134a refrigerant. As we both said, an AC shop will be able to sort things out. Also, from the "tone" of your message, I seem to infer that you want to do an AC re-charge yourself. It's easy to "top-off" an AC system with refrigerant with those kits they sell - but evacuation and making sure you have the proper amount (especially not too much) of oil in the system are other matters. Part of the annual service on your Ferrari is supposed to include an evacuation and re-charge of the AC system. The system is evacuated/re-charged to provide a change/volume check of the compressor oil and to remove the old refrigerant. The refrigerant is highly hygroscopic (absorbs water) and it becomes "corrosive" and has reduced cooling capacity when it is contaminated with water . You can check for this at the sight glass on top of the AC dryer unit when the system is running. If you see "milky" refridgerant - you probably have water in your system.
The Ferrari AC system is nothing special, just very, very expensive. IMHO, I would let an AC shop do the charging/evacuation of the system. However, as they say, it's your car. Best of luck.

 

I think most of us on FChat like to do as much work as possible on our cars. However, for proper AC service you really need an AC Charging Station (with vacuum pumps, refrigerant collection vessel, etc.). Having the proper tools/equipment frequently makes all the difference in the World when it comes to the overall quality of the results. As much as I don't like to, I bite-the-bullet and go to an AC shop when it comes to charging/recharging my AC system.

P.S. The only thing stupid about your original question would have been NOT to ask it! There are incredibly knowledgeable people on FChat! I learn somthing new every time I log-on.

 

My question is a 355. I don't have the car in front of me so I have to ask till the next time I see it. Does the 355 have the same "windows" that are on the 348 to determine when the proper amount of refridgerant? I assume this is under the lining in the front bonnet? I have a friend that has a/c experience. He evacuated my a/c and now it's time to refill it. His questions to me were how much refridgerant does it need (18-24oz?) and not as important - what are the proper pressures?

I saw a howto on this earlier for the 348 but computers being as they are I wasn't able to save it and had to close the browser. I will search again for it later.

 

...one more question. I'm told that the foam watching procedure is not a good indicator for r134a and that knowing the proper capacity is much more critical. Is this accurate?

 

There are a few ways to charge the a/c system.

1-Correct amount of weight of gas.
2-Guessing by setting to the pressures.
3-By "feeling" the a/c pipes.
4-By "feeling" how cold the air is in the cab.

Of course #1 is the BEST way. But not everyone has access to scales to charge the a/c properly.

I dont have scales at home, so I have to guess the amount of gas in the system by the pressure. Low side should be between 15-30 psi and the high side between 250-300 psi.

I use scales at work to fill with the correct amount of a/c gas. And trust me, it is the best way to service a/c systems.


Nearly every receiver-drier has a sight glass so you can see bubbles/gas flow through it.

Also, if you watch the sight glass on the receiver-drier you may see the bubbles in the a/c system. If you see bubbles, keep filling with gas till the bubbles are gone and the sight glass is clear. Not the best way to do it, but can be done what way.

Any of those ways will get you cold air mate. If you have access to scales, do it that way. If not, check the pressures, check the sight glass on the drier. If you had easier access to the a/c pipes, you could "feel" them to see how cold they are getting.

 

PAP is the expert here and I used his advice when servicing my 575M's air conditioner. Part of the problem could be a dryer/filter that is way past its service life. Ferrari calls for the dryer/filter to be replaced, along with the refrigerant, every two years. Overkill on the dryer/filter, but PAP and FBB explained to me that a really good vacuum pull (possibly overnight) by a knowledgable shop before refill with refrigerant will really improve A/C efficiency. And, lo and behold, they were right. You can make ice cubes in my car from following their advice. Including a new dryer/filter.

Taz
Terry Phillips

 

Great to hear Taz!!

 

<snip>If it is an older system you may have to convert to R134a, although it is still possible to find shops/HVAC techs that still have a "store" of R12 "in the back". However, it is supposed to be illegal to fill car systems with R12 now. If R134a was used and it did cause damage to your system, then it might be quite expensive. <snip>


R12 is still availible just more expensive than R134A. It is NOT illegal to charge a car originally designed for R12 to recharge it with R12. R134A has smaller molecules than R12 so it is reccomended to install barrior hoses to hold it in better. Also different o-material is reccomended. Different oil is also used. The biggest problem with R134 is that the head pressures that the compressor is subjected to are much higher. So when changing to R134 it is best to install a new compressor, reciever dryer and expansion valve. Also flush the hoses/lines free of the old oil. It is also suggested that you put in ten percent less weight of R134 than the speced R12.

The biggest problem with R134A is that it does not transfer heat as well as R12. So using R134A in a R12 system will cause it to not cool as well. Cars designed to use R134A have larger condensors and evaporator cores to exchange more heat. Even with the larger cores the dash vent temps in R134A systems are not as cold as an R12 systme that is working properly.

By law any shop that does AC work is supposed to have a refridgerant identifier. It takes a sample and tells what percent is R12, R134 atmosphere or some other oddball gas.

If your car still has R12 fittings I would repair leaks as needed, install a new receiver dryer and have it charged with genuine R12. Not some other "replacement" for R12.

 

Grab a flashlight. Go to the front of your 348 and drop down onto your knees. Shine the light into the A/C inlet hole (the asymmetrical opening on the bottom of the front bumper, passenger side.

Look for caked mud or obstructions. I've had an entire newspaper sucked up into there. Let me tell you, that stops the cooling power pretty darn fast!

Free fix, if so.

 

ND- There you go getting practical again. Good advice.

Pap- I am not too bright, but I do listen. It pays off.

Taz
Terry Phillips

 

My reasearch showed the US cars got the 134a in 1995. For what it's worth mine has a light green plastic tag in the engine bay where the ac line goes into the firewall. The tag says R134a on it with a ferrari logo. From the rear of the car look to the right of the motor towards the bottom of the FWall. If the tag is there it takes some guess work out of it. I was never able to confirm the EXACT change over date at the factory but i did find the 95's have it but some 94's might also depending on date of prod.

Ben