Air Condition Gas Type

Post here for mechanical and engine topics such as fuel issues, transmission problems, rough idle, exhaust, electrical issues, etc

Moderators: GRNSHRK, ron, bfons

Post Reply
User avatar
Sharknose
Posts: 170
Joined: Mon Jul 29, 2013 9:36 pm
Location: Cd. Juarez, Mexico

Air Condition Gas Type

Post by Sharknose »

OK, here I go again hoping someone can help me out with my ignorance when it comes to A/C leaks and gas types.
A year ago I checked the A/C in my '89 sixer which was working well, compressor blowing fairly cold air \:D/
This year (which is one of the hottest ever here in northern MX) just warm air is blowing :evil: . I went to my shop technician and he checked the entire A/C of any leaks. He couldn't find any and mentioned it might be the compressor that loses gas while working (?!) :roll:
He then suggested to get one of these oil based A/C Stop Leaks (e.g. Red Angel) to fix the issue. He insisted on R12 (which was banned around 1990 or so - hard to find stuff ](*,) )
My question is 2 fold:
Any feedback on the stop leaks "stuff" and if it is working for "minor" leaks?
What's the deal with the A/C gas types? Could I use R134A instead? :-k
I read this:
635 SERIES
1989 All Engines w/ Front & Rear AC ... Type R12 63.50 Oz. Mineral 5.75Oz.
What about this?:
There are number of alternative refrigerants from which to choose. One is R-134a, which is the ONLY alternative refrigerant currently approved by all vehicle manufacturers for retrofitting older R-12 A/C systems. The vehicle manufacturers say R-134a will cool reasonably well in most R-12 A/C systems provided the proper retrofit procedures (what are those?) are followed. They also recommend R-134a because it is a single component refrigerant, unlike most of the alternatives which are actually BLENDS of two to more ingredients.

Bonus question:
How about the hoses? I heard some gases may be different and might "creep" through them?! :-({|= Should all the hoses perhaps be replaced with newer ones? They say "Have lines rehosed once with a good barrier material ( like what?) and never worry about them again".

Many thanks in advance for any feedback on this...
Sharknose
1989 BMW 635CSi - Metallic Smoke Gray - my Lupita

"If it weren't for the last minute, nothing would get done!"
rhanley 635csi89
Bigcoupe Contributor
Bigcoupe Contributor
Posts: 323
Joined: Wed Sep 10, 2014 12:08 am
Location: Arden, NC 28704

Re: Air Condition Gas Type

Post by rhanley 635csi89 »

Read the post at Bimmerforum24 on A/C, It covers most options available today on A/C upgrades.

http://www.bimmerforums.com/forum/showt ... S-OF-2016)
89 635CSiA (11/88 build)
AlpineWeiss II (218)/Natur(0200)
87 L6 635CSI Sold
87 MB 560SL Sold
User avatar
Da_Hose
Platinum Member
Platinum Member
Posts: 3236
Joined: Fri Mar 07, 2008 8:15 am
Location: Santa Ana, CA.

Re: Air Condition Gas Type

Post by Da_Hose »

Do some reading and searching. We have lots of posts about this. That said, do not use a stop leak product. Ever! [-X
Add gas and dye, then identify where it is leaking from and address it correctly.

If it is leaking from the compressor, try to find an OEM replacement and use R-12. If you cannot find R-12, then you should do the conversion right. Get a parallel flow condenser, replace parts as necessary, change hoses to modern barrier type, refill with PAG oil, and convert to R134.

Jose
1987 M6 - My dream car
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

To repeat, never use any stop,leak compounds, ever. If you can get R12, that's your first, and best choice, since that's what the system was designed for. If not, R152a is a great newer refrigerant, and it's cheap and readily available. In any case, a PF condenser will always improve the system performance. Even with a PF condenser, R134a will not work as well as R12 or R152a.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
jacko
Posts: 416
Joined: Mon Feb 03, 2014 6:43 pm
Location: DFW Texas

Re: Air Condition Gas Type

Post by jacko »

I converted and mine blows colder now!

Reseal the ducts in the dash.
Running 2 PF condensers
Used a 7 piston Sanden compressor
New hoses.

Both front and rear units will freeze you out.

I still have to get around to finishing the e39 fan swap.
Jack
Arlington, Texas. USA

1989 635csi
Automatic
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

jacko wrote:I converted and mine blows colder now!

Reseal the ducts in the dash.
Running 2 PF condensers
Used a 7 piston Sanden compressor
New hoses.


Both front and rear units will freeze you out.

I still have to get around to finishing the e39 fan swap.
Because you did it correctly!
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
User avatar
Da_Hose
Platinum Member
Platinum Member
Posts: 3236
Joined: Fri Mar 07, 2008 8:15 am
Location: Santa Ana, CA.

Re: Air Condition Gas Type

Post by Da_Hose »

You have a butt kicking setup, Jacko!

Jose
1987 M6 - My dream car
Pod
Platinum Member
Platinum Member
Posts: 4492
Joined: Tue Mar 16, 2010 8:32 pm
Location: usually in the barn, Kent, England.

Re: Air Condition Gas Type

Post by Pod »

Sharknose wrote:
Bonus question:
How about the hoses? I heard some gases may be different and might "creep" through them?!
As I understand it, R134a has a smaller molecular structure than R12 which is why it leaks out. I stand to be corrected though!

I've had American cars with R12 which has always worked with never a recharge, but R134a? Forget it, no way is it as good IMO.

So I wonder, is it better for the planet to use R12 which has been banned, but seldom leaks...or R134a which will always need to be topped up (in my experience!)?
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

From what I've read, R134a has been shown to be just as harmful to the environment, and R152a will be the replacement that's on the horizon for all new cars. R152a works great, and operates at lower system pressures, too, which extends compressor life, and uses less HP. I'm going to have to open my system up sometime soon, to adapt an E39 fan to the condensor, and my next refill will be with R152a, even though I still have a small stock of R12.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
User avatar
Da_Hose
Platinum Member
Platinum Member
Posts: 3236
Joined: Fri Mar 07, 2008 8:15 am
Location: Santa Ana, CA.

Re: Air Condition Gas Type

Post by Da_Hose »

The flammability of R152a prevents me from risking the changeover. The AC lines are inches away from the "will sear your face clean off" levels of heat emanating from the Euro headers. I do have a heat shield on now though, which I suppose might make using R152a of less concern.

Hmmm...... might need to get in there and check heat with my IR thermometer. It is really hot right now, so this would be a good time to gauge what the high end temps. would look like.

Jose
1987 M6 - My dream car
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

I took a can of Dust-off outside and tried to get the vapor stream to ignite using my propane torch lighter, and I couldn't do it. Then I lit the torch and sprayed the Dust-off into the torch flame. It did ignite, but went out if I moved it away from the torch flame. I tried turning the can upside-down to get a liquid stream, and that will also ignite in the torch flame, but it sputtered out when i took it away from the torch. So, yes, it is flammable, but not nearly enough for me to worry about, especially since it won't sustain a flame on its own, and it isn't explosive. The gases from the flame are extremely toxic, however.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
User avatar
slofut
Posts: 778
Joined: Thu May 30, 2013 1:29 am
Location: SW Ga

Re: Air Condition Gas Type

Post by slofut »

dwcains wrote:I took a can of Dust-off outside and tried to get the vapor stream to ignite using my propane torch lighter, and I couldn't do it. Then I lit the torch and sprayed the Dust-off into the torch flame. It did ignite, but went out if I moved it away from the torch flame. I tried turning the can upside-down to get a liquid stream, and that will also ignite in the torch flame, but it sputtered out when i took it away from the torch. So, yes, it is flammable, but not nearly enough for me to worry about, especially since it won't sustain a flame on its own, and it isn't explosive. The gases from the flame are extremely toxic, however.
There ya go Dean! I suspected as much, but had not done any back yard testing. It would be fun to toss a can in a bonfire (done this) :shock: , or spray it under a bucket with a long fuse, just for further testing...

Another question though, are 12a and 152 similar gasses? Just thinking about having it serviced by other shops. With 152 I feel like I'll need my own vacuum pump, got 12/134 guages. But I wouldn't want to contaminate someone elses recycle equipment etc... Thoughts?
Bill
'87 635csi, 5sp man, dk blu on pearl beige
'88 635csi, auto, black on grey
'63 BMW Isetta
'75 XJ6C, 2dr, warm 350
'86 XJ6, th700r4
'75TR6
'64 Olds 88 conv
"68 T120 Bonneville
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

R12 and R152a are very different gases (not sure there is a fixed formula for R12a, which is usually a hydrocarbon mix), but if your system already empty and you hook to a vacuum pump, you're not contaminating anything, as the pump just vents to the atmosphere. Shops do have refrigerant recovery equipment, but I don't know if they'll use it if they're not sure what's in the system, and I don't know how they make that determination. Gauges don't get contaminated, as the gas in the hoses dissipates into the atmosphere when you disconnect them. You'd use ~54% by weight R152a as compared to R12, but some fine-tuning is needed if you have a different condensor, which may have a different volume. I'm not sure if a shop will install R152a yet, although is supposedly approved as an R134a alternative in automotive a/c. The guy who evacuated my system last year had no idea what I was talking about when I asked him about R152a, but at that time we charged it with R12 anyway. He was actually hesitant to use the R12 I had, and mentioned that there are counterfeit cans of R12 out there, filled with propane or something else.

I'm thinking about buying a vacuum pump, just so I can do everything myself. Looked at a few on Amazon and there are some on the local craigslist, too. Looks like a suitable one can be had for under $100.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
User avatar
slofut
Posts: 778
Joined: Thu May 30, 2013 1:29 am
Location: SW Ga

Re: Air Condition Gas Type

Post by slofut »

dwcains wrote:R12 and R152a are very different gases (not sure there is a fixed formula for R12a, which is usually a hydrocarbon mix), but if your system already empty and you hook to a vacuum pump, you're not contaminating anything, as the pump just vents to the atmosphere. Shops do have refrigerant recovery equipment, but I don't know if they'll use it if they're not sure what's in the system, and I don't know how they make that determination. Gauges don't get contaminated, as the gas in the hoses dissipates into the atmosphere when you disconnect them. You'd use ~54% by weight R152a as compared to R12, but some fine-tuning is needed if you have a different condensor, which may have a different volume. I'm not sure if a shop will install R152a yet, although is supposedly approved as an R134a alternative in automotive a/c. The guy who evacuated my system last year had no idea what I was talking about when I asked him about R152a, but at that time we charged it with R12 anyway. He was actually hesitant to use the R12 I had, and mentioned that there are counterfeit cans of R12 out there, filled with propane or something else.

I'm thinking about buying a vacuum pump, just so I can do everything myself. Looked at a few on Amazon and there are some on the local craigslist, too. Looks like a suitable one can be had for under $100.
Was actually asking about r12a as opposed to r12. 12a being a propane/butane mix, seems like is similar to 152a. Just wondering if it's close and why not just use 12a if it is? (as it's on the shelf and I suppose fittings are same as 134?)
btw... I have no prob using 152a if it will cool better than 134a
'87 635csi, 5sp man, dk blu on pearl beige
'88 635csi, auto, black on grey
'63 BMW Isetta
'75 XJ6C, 2dr, warm 350
'86 XJ6, th700r4
'75TR6
'64 Olds 88 conv
"68 T120 Bonneville
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

I wasn't sure if you were asking about R12a, sorry. I've had no experience with it, but it does seem to get a lot of use. I never really reasearched or considered it, simply because I had plenty of R12. The appeal of R152a is that it's readily available and inexpensive, but the best thing is the lower system pressures and less strain on the compressor.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
User avatar
Da_Hose
Platinum Member
Platinum Member
Posts: 3236
Joined: Fri Mar 07, 2008 8:15 am
Location: Santa Ana, CA.

Re: Air Condition Gas Type

Post by Da_Hose »

Yes, R12a is an isobutane and highly flammable, but it has been used in many other countries and is legal for you to use as a retrofit. However, if R152a has such low flammability, then I don't see any reason not to use it for our systems. If your compressor has PAG oil, you could go have your R12 or R134 evacuated and just swap in the gas.

Jose
1987 M6 - My dream car
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

I'm going to open the system up again sometime soon, as I want to adapt an E39 fan to the condensor, and that will be easier with the condensor out of the car. The local pick and pull yard has a good stock of recent BMW's in, so I'm going to see what I can salvage this Monday. When I get the system back together, I'll flush it (not sure what oil is in there with the R12), and then refill with the R152a and some double-end-capped PAG oil. Then I'll see if I can get the a/c working in my '92 Alfa Spider, which should be a fun project.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
User avatar
Sharknose
Posts: 170
Joined: Mon Jul 29, 2013 9:36 pm
Location: Cd. Juarez, Mexico

Re: Air Condition Gas Type

Post by Sharknose »

Has anyone any experience with this brand as a R12 replacement? :shock: :-k

Freon™ MO49Plus refrigerant
This is what they say about this stuff on the net:

Freon™ MO49Plus (R-437A) is an HFC retrofit refrigerant for R-12 in automotive air conditioning and stationary refrigeration systems, and for replacing HCFC-containing refrigerant blends (e.g., MP39, MP66, and R-409A) in stationary refrigeration systems. Freon™ MO49Plus is compatible with traditional and new lubricants; in most cases no change of lubricant during retrofit is required.

Freon™ MO49Plus is not recommended for use in centrifugal compressor systems or for chillers with flooded evaporators or low pressure receivers.

Note: Freon™ MO49Plus is not available for automotive air-conditioning in the U.S. [-X


ASHRAE
R-437A; A1 Safety Classification.
Freon™ MO49Plus has an ASHRAE safety classification of A1 and is non-flammable as formulated and under leakage scenarios as specified in ASHRAE Standard 34-2007. Refer to the Safety of Refrigerants bulletin and the Safety Data sheet for details.

Replaces
Freon™ MO49Plus replaces R-12, HCFC-containing blends (e.g., MP39, MP66, and R-409A).

Applications
Automotive AC systems designed for R-12
Refrigeration systems designed for R-12, including: Food service
Supermarket display cases
Food storage and processing
Domestic refrigerators/freezers

Benefits
Provides cost-effective retrofits Replaces R-12 and HCFC-containing blends, such as MP39, MP66,
and R-409A
Replaces R-413A
Non-ozone-depleting HFC retrofit refrigerant Not subject to phaseout under the Montreal Protocol
Compatible with traditional lubricants In most cases, no change of lubricant type is needed
Enables continued use of existing equipment

Performance
Provides similar to slightly lower efficiency vs. R-12
Provides lower discharge temperature vs. R-12

Phase-out Schedule
Freon™ MO49Plus is a non-ozone-depleting substance (ODS) and, therefore, is not subject to phase-out under the Montreal Protocol regulations.

Lubricant Recommendation
In automotive air-conditioning and stationary refrigeration systems, Freon™ MO49Plus is compatible with traditional and new lubricants. In most cases, no change of lubricant type during retrofit is needed. Refer to the Freon™ MO49Plus Retrofit Guidelines (for Stationary Refrigeration or Automotive AC) for details.
Sharknose
1989 BMW 635CSi - Metallic Smoke Gray - my Lupita

"If it weren't for the last minute, nothing would get done!"
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

Looks OK, and it's made by Chemours (ex-DuPont), so I would expect it to work as described. Where/How do you buy it? Do you have to buy a 25 lb. cylinder, or can you get it in small cans?
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
User avatar
Sharknose
Posts: 170
Joined: Mon Jul 29, 2013 9:36 pm
Location: Cd. Juarez, Mexico

Re: Air Condition Gas Type

Post by Sharknose »

Well, here in Mexico you can get them in 750ml spray cans. 8-[
My shop tech. has just added it to my sixer and it works very well. If it fails, I'm just back to a non-working A/C #-o , but so far it's freezing cool. \:D/
Attachments
DuPont ISCEON MO49Plus - 750ml.PNG
DuPont ISCEON MO49Plus - 750ml.PNG (331.09 KiB) Viewed 11878 times
Sharknose
1989 BMW 635CSi - Metallic Smoke Gray - my Lupita

"If it weren't for the last minute, nothing would get done!"
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

Good for you - glad you've got working a/c in your 6, and that it was so easy.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
masonjones
Posts: 50
Joined: Sun Mar 02, 2014 1:29 am
Location: Austin, Texas

Re: Air Condition Gas Type

Post by masonjones »

dwcains wrote:I'm thinking about buying a vacuum pump, just so I can do everything myself. Looked at a few on Amazon and there are some on the local craigslist, too. Looks like a suitable one can be had for under $100.
I can vouch for this one from Harbor Freight. It works well and it's in their current flyer for $89.
http://www.harborfreight.com/25-cfm-vac ... 98076.html
1985 635CSi
User avatar
slofut
Posts: 778
Joined: Thu May 30, 2013 1:29 am
Location: SW Ga

Re: Air Condition Gas Type

Post by slofut »

Just came across this bit, will come in handy. Not expensive either...


http://viot.us/showproduct.php?model=BA3&sw=0

and this

http://www.ebay.com/itm/HVAC-Tool-Kit-2 ... xyqKVRiZVm
'87 635csi, 5sp man, dk blu on pearl beige
'88 635csi, auto, black on grey
'63 BMW Isetta
'75 XJ6C, 2dr, warm 350
'86 XJ6, th700r4
'75TR6
'64 Olds 88 conv
"68 T120 Bonneville
User avatar
dwcains
Posts: 1465
Joined: Sun Sep 14, 2014 6:01 am
Location: Lutz, FL

Re: Air Condition Gas Type

Post by dwcains »

masonjones wrote:
dwcains wrote:I'm thinking about buying a vacuum pump, just so I can do everything myself. Looked at a few on Amazon and there are some on the local craigslist, too. Looks like a suitable one can be had for under $100.
I can vouch for this one from Harbor Freight. It works well and it's in their current flyer for $89.
http://www.harborfreight.com/25-cfm-vac ... 98076.html
Thanks, I'm going to HF tomorrow to pick up a vibratory polisher, so I'll have a look.
Dean
Lutz, FL

'85 635 CSi Euro #9402254
'87 Spider Veloce
'92 Spider Veloce
'08 350Z

Image
Post Reply