R12 to R34 Converstion
- Thread starter LIRacer
- Start date
Martin72
Active member
Yes....there are kits available to convert from R-12 to R-134a. Go to any parts store (I got mine at Advance Auto Parts). The kit will contain 3 cans of Freon/oil/seal conditioner mixture, a charging hose, and adapters to fit your fittings....BUT....
The adapters will not fit on your car! You will need to get a set for an early GM car (both hi-pressure and low-pressure connections on your car are the same -- late model GM's and others have different size fittings). If they don't have them in stock, they can order and have them in a day.
Now, once you drain all the R-12, and vacuum the system (if possible), just follow the instructions with the kit. You will need to figure the amount of R-134a to use. There should be a sticker that states how much R-12....then only use 80% to 85% R-134a.
Another little problem....the POA valve tries to limit the suction pressure to 25 to 30 psig.....R-134a works best at 35 to 45 psig. You system will still work, but the temp out of the vents will be in the 45 to 50 degree range. Cool, but not as cold as the later models will get.
Good luck....
The adapters will not fit on your car! You will need to get a set for an early GM car (both hi-pressure and low-pressure connections on your car are the same -- late model GM's and others have different size fittings). If they don't have them in stock, they can order and have them in a day.
Now, once you drain all the R-12, and vacuum the system (if possible), just follow the instructions with the kit. You will need to figure the amount of R-134a to use. There should be a sticker that states how much R-12....then only use 80% to 85% R-134a.
Another little problem....the POA valve tries to limit the suction pressure to 25 to 30 psig.....R-134a works best at 35 to 45 psig. You system will still work, but the temp out of the vents will be in the 45 to 50 degree range. Cool, but not as cold as the later models will get.
Good luck....
- Thread starter
- #3
HammerDown
Well-known member
How about Freez-12 ? I've herd nothing but good about it. And colder than the 134A.
I was looking around for the 401B refrigerant. I read a positive recommendation by "Burglar" (I believe..); however, I could not find anyone seelling nor servicing the 401B.
I ended servicing the car with FR-12. It's supposed to be like R-12 but without the ozone-killing propelant. It works good, just about the same as the R-12. ...:L...it's been so long that I have not had the A/C turned-on that I forgot how cold it used to get or not get.
I ended servicing the car with FR-12. It's supposed to be like R-12 but without the ozone-killing propelant. It works good, just about the same as the R-12. ...:L...it's been so long that I have not had the A/C turned-on that I forgot how cold it used to get or not get.
Tom73
Well-known member
Check out this EPA page if you are considering using something other than R12 or R134a.
http://www.epa.gov/spdpublc/snap/refrigerants/macssubs.html
Some mentioned Freez 12. It is a blend made up of 80% 134a and 20% 142b. So...80% 134a, then why not go with 134a???
What about FR-12? It is also a blend, 59% 134a, 39% 124, and 2% Butane (yep butane). Also 124 is the refregrent that REQUIRES the use of barrier hoses. So will need to replace the hoses.
401B? Per the EPA site: "...have not been submitted for review in motor vehicle air conditioning, and it is therefore illegal to use these refrigerants in such systems as an alternative to CFC-12. "
R-12 is more expensive but it is readily available. If the A/C system is operating correctly then a refill should be a one time expense. The C3 system was designed to use R-12. So why not stay with it???
tom...
http://www.epa.gov/spdpublc/snap/refrigerants/macssubs.html
Some mentioned Freez 12. It is a blend made up of 80% 134a and 20% 142b. So...80% 134a, then why not go with 134a???
What about FR-12? It is also a blend, 59% 134a, 39% 124, and 2% Butane (yep butane). Also 124 is the refregrent that REQUIRES the use of barrier hoses. So will need to replace the hoses.
401B? Per the EPA site: "...have not been submitted for review in motor vehicle air conditioning, and it is therefore illegal to use these refrigerants in such systems as an alternative to CFC-12. "
R-12 is more expensive but it is readily available. If the A/C system is operating correctly then a refill should be a one time expense. The C3 system was designed to use R-12. So why not stay with it???
tom...
- Thread starter
- #7
Martin72
Active member
I would have recharged with R-12 (I still have about 15 lbs left), but since the expansion valve was plugged and the compressor hoses were bad....I had to pull most of the system out to clean, I wanted to convert to R-134a to see just how it worked. I've heard the stories, but wanted to see for myself.
IF I ever pull the system apart again, I'm going to increase the spring pressure in the POA to increase the suction pressure up to the 35 to 40 lbs that R-134a likes to see if that helps the cooling.
Like Tom73 said earlier....stick with R-12 or convert to R-134a....but stay away from the "other stuff".
IF I ever pull the system apart again, I'm going to increase the spring pressure in the POA to increase the suction pressure up to the 35 to 40 lbs that R-134a likes to see if that helps the cooling.
Like Tom73 said earlier....stick with R-12 or convert to R-134a....but stay away from the "other stuff".
C
CS72Roadster
Guest
I had mentioned this in another topic but thought I'd post a link for those not aware of this.
http://www.imaca.org/index.htm
For 15 bucks you can get the certification required to buy r12 freon. R12 is available on Ebay for 15-20 bucks a can.
CS
http://www.imaca.org/index.htm
For 15 bucks you can get the certification required to buy r12 freon. R12 is available on Ebay for 15-20 bucks a can.
CS
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