R12 in AZ
- Thread starter phxtlc
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You can do it yourself and switch it over to R134a with the bottles of R134a from Walmart, Autozone or almost any other auto parts store. They even have the leak detector stuff so you can pin point where your system is leaking. HTH
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TX_TLC said:
You can only buy R-12 if you are certified to do so, you can however still buy 134-A w/o certification but it is not compatable with an R-12 system.
It's compatible with some slight modifications.
Very slight, and sometimes none.
And certification for R-12 involves taking a written test.
-Spike
And certification for R-12 involves taking a written test.
-Spike
rick_d said:
R-134 only has issues in cars with small condensers. I don't have specific information, but the LC shouldn't suffer in that area.
-Spike
-Spike- said:
I would respectively disagree with that. There are a number of complaint on AC performance of the late model R134-equipped LC and LX450. Granted, it could also be constributed by the fact that Toyota deem fit to not equipt the US/NA market 80-series with the rear AC and the aux condensor fan.
R12 all the way in AZ -
I have 2 cruiser that run on R12 and provide the coldest AC of all my junk. I will run R12 for ever until it is no longer available or untill the 33lbs of R12 in my garage runs out.
I have 2 cruiser that run on R12 and provide the coldest AC of all my junk. I will run R12 for ever until it is no longer available or untill the 33lbs of R12 in my garage runs out.
-Spike- said:
R-12 aircons need large modifications to use 134-A. 134-A has much smaller molecules than R-12 and if you fill your R-12 system with 134-A you will experience success for at most a month after which it will have leaked out enough to be ineffective. That was my experience when I tried to change from R-12 to 134-A simply by draining out the R-12 and pumping in the 134-A. 134-A's smaller molecules find leaks which don't exist for R-12 and the best way to convert is to change your system including compressor and fittings ( Effectively the whole air con ). I had to return to R-12 as I didn't want to spend for a new air con.
Kalawang
Shhhh
Dont tell this to my 92 as its been running R134a in it for over 5 years and 50k I havent had to top it off yet
Dont tell this to my 92 as its been running R134a in it for over 5 years and 50k I havent had to top it off yet
Kalawang said:
http://search.ebay.com/r-12-refrige...gerantQ20Q2d134aQ20r12QQsbrftogZ1QQsofocusZbs
no gud html skilz'
I have run both, 34F degrees at vent for R12 and a luke warm 39F with r134a.
yea, no difference....
no gud html skilz'
I have run both, 34F degrees at vent for R12 and a luke warm 39F with r134a.
yea, no difference....
I've noticed a difference with my '93 in Boise (~100F & dry regularly in summer) between R12 and R134a, but my converted system is working acceptably.
Kalawang said:
No offence meant, but that's just wrong.
R134a and R12 are not all that far apart as far as molecular structure or weight is concerned. R12 is CCl2F2 whereas R134a is CF3CH2F (sorry, but can't do subscripts--the numbers are subscripts); they're both halocarbons, but one is a one-carbon and the other is a two-carbon molecule. R12 has a molecular weight of 121 and R134a's is 102, so there's not much difference; yes, it is maller, but it's not sufficiently smaller to enable anything you'll find in your truck to differentiate (meaning your A/C will leak no more R134a than it would R12).
FWIW, the structure of freons is defined pretty well as follows (fyi, aliphatic carbon has four bonds, so each carbon atom has to have four other atoms attached):
R simply stands for refrigerant
Expect three digits; if only two, it means there is only one carbon
*First digit is one less than the number of carbon atoms (in the case of a one carbon molecule, this digit is left off, leaving you with a two digit number)
*Second digit is one more than the number of hydrogen atoms.
*Third digit is the number of fluorine atoms.
*Any remaining atoms are assumed to be chlorine atoms.
*The lowercase suffixes represent progressively unbalanced structures as determined by the molecular weights of the end elements.
For example, R12 is: [Cl2CF2]
Cl
|
Cl - C - F
|
F
and R134a is:[CF3CH2F]
F
|
F - C - F
|
H - C - H
|
F
The reason for the "a" designation is that for a balanced structure, the fluorine atoms would be distributed evenly, not three on one carbon and one on the other.
EDIT: Dman system won't allow indents, so the structures look fauked up. The verticle lines and atoms above and below them are supposed to be lined up the the C atoms. Oh well...
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Kalawang said:
Sorry you had a bad experience, but I stand by my earlier statement. Most systems will run satisfactorily after being converted to R-134 with very little equipment change. I believe the system should be flushed to clean out the r-12 compatible oil. The dryer should be changed, and changing the expansion valve will give better results. I have heard of a variable expansion valve that will adjust to changing pressure resulting from engine RPM changes, and it's supposed to work with both refrigerants (or they have them for both, I disremember) giving improved performance at idle and high RPM.
I'm no A/C expert, so if someone is thinking of going this route I encourage you to search Google for more information.
-Spike
I drive a 1992 which appears to have been professionally converted to R-134a, and it seems to be at least as cold as our other 2 vehicles with factory R-134a systems. I have zero complaints about R-134a performance in a vehicle with a suitably large condensor, which can hide the slight disavantage in cooling efficiency.
If you convert, my personal recommendation is a professional job, as the solvent used to flush the R-12 oil from the system is rather unhealthy. Also, if a proper flush and vacuum job isn't performed, the odds of the compressor seals wearing and leaking prematurely increase.
R-134a uses a different lubricating oil; thus the advice by many to replace every last o-ring (including those in the evaporator behind the dash) with fresh, uncontaminated o-rings when converting. IIRC, this is the same reason the filter/dryer must also be replaced.
A few good FAQs and forums on the web regarding this topic were highly informative when I converted my former DD/beater.
If you convert, my personal recommendation is a professional job, as the solvent used to flush the R-12 oil from the system is rather unhealthy. Also, if a proper flush and vacuum job isn't performed, the odds of the compressor seals wearing and leaking prematurely increase.
R-134a uses a different lubricating oil; thus the advice by many to replace every last o-ring (including those in the evaporator behind the dash) with fresh, uncontaminated o-rings when converting. IIRC, this is the same reason the filter/dryer must also be replaced.
A few good FAQs and forums on the web regarding this topic were highly informative when I converted my former DD/beater.
-Spike- said:
In actuality it wasn't me alone. and the two units were both JDM's set for R-12 and both had the same systems and both leaked but the problems went away after re-converting back to R-12. We had also been advised that we could do the change and our only explanation after was what I gave. 134-A is 5x the cost of R-12 here but we wanted to do our bit for the greenhouse thing.
Your's and other info given here tells me I need to rethink my experience. The short time I had 134-A gave me much the same cooling as R-12 so only the cost of conversion stands in my way.
Kalawang
FJ809496TLC
80 series addict
R134a works in a higher pressure that might cost for some system to leak.Have your system pressurized and leak tested before using the new freon. Based on my personal experiences, R12 gives better cooling than R134a in extreme hot weather. 
