Lightfoot

Bought a retro-kit at AutoZone friday and changed the 65's A/C to the new 134A. The kit was only $34.99 + tax for the refrigerant, adapters, guage, and hoses. A friend with a 93 ruby lost his AC on his way to Bg this weekend and did the same thing. I will have to admit, i was skeptical, but after talking with him, i decided to give it a try. The A/C is now cooling better than it ever has, and (the good part) left all the original system intact. just had to add an adapter to introduce the new oil and 134a. Drove it all weekend with the AC on!!! man what a difference. And of course, never forget to get the certified technician to remove all the old freon first.
Cruisin Cooooool in BG!
Lightfoot

yooperod

Great, Let us know now it holds up. I've heard various reports that it will
eventually leak out of axial ac compressors.
I have used it with radial compressor with good results.
I'm gonna have to charge the '74 when I get it on the road.
and I figured with the price of r134 a few recharges is afforable.
(I can do it myself) rod

SWCDuke

My understanding of the conversion issue is that R134a and/or the synthetic oil used with R134a is not compatible with the mineral oil lubricant used with R-12, and in order to purge as much of the mineral oil from the system as possible, you need to evacuate the system for several hours, preferably overnight. Liquids cannot exist in a vacuum, but a low vapor pressure liquid like oil will take some time to evaporate even if you can pump the system down to less than 1" hg absolute pressure.

Some also advocate flushing the system with a solvent and then re-evacuating.

My question is how did the tech prep your system for the R134a and new synthetic oil. Did he keep the vacuum pump on it overnight?

If there are incipient problems, they will take time to develop. R134a is a smaller molecule, which can more easily escape on older systems, so a R134a charge will probably not last as long, but even if it has to be recharged twice as often, it's probably cheaper, as long as there isn't enough of the old oil in the system to cause problems.

Duke

joevette57

I've converted several a/c systems. The freon will not leak out of the compressor if it's in decent condition. Where it WILL leak is through old hoses, and non-crimped connections such as those made with hose clamps. The 134 molecules are smaller than R-12 and can get through places that the 12 could not.

pittsaj

Keep us up to date on this one...

With the very high cost and almost nonexistant R-12

I'm sure there are many of us that would like to know the details on the conversion and the results..

What are the new operating preasures???
Is cooling as good as R-12?

I've heard there are R-12 replacements like FR-12 and Freeze-12 but these are hard to get as well..

Since we all work on our own cars...
We really need something that we can get hold of ourselves..

Any Refrigeration A/C experts out there??
What do you think of these other refrigerant replacements

Tony



[Modified by pittsaj, 9:45 PM 9/2/2002]

Ih2lose

I have converted many cars from r12 to 134a very succesfuley.I have a note book on it.I always install a new refrig drier in the system and use a chemical that is a flusher of the old oil,and then flush with nitrochen witch is a inert gas.As duke has mentioned the dehydration of the system and oil removal is important .I also go into a deep long vacum I have a comercial vacum pump 2 stage (6cfms) I have not had to add any refrig to any of the sytem's I have converted any leaks we found and corrected at the time.All of the cars I have done so far have been freinds collector cars.I also charge by reducing the original charge to 80% and it has worked out well.I had charged my 1967 caddy by sight glass (it has a poy valve in it ) and found that it was grossley over charged.I recovered the gas and then recharged it to 80% and it works fine.
You never realize how important a/c is untill you get stuck in a rain strom and cant see out the windows with out the dehumidifacation.
CAUTION
When R12 was being fazed out one of the first replacements was a refrigerant that was made of a highley explosive propane based gas so becarefull when recovering the old gas if any is left.
Most refregerant gas's are not explosive BUT they are poisonous when exsposed to a flame creating a gas called fosgine (like the old mustard gas) witch is very poisonous/fatal.When I was learing the trade I was not aware of the dangers of fosgine and got poisened while doing a repair.If not for my wife/girlfreid at the time visiting me at my job site and noticing my strange behaveour,nose running uncontrolabley and incoherent. I would have died.
I spent 8 days in intensive care.so please be carefull! what you dont know can kill you!
My proffetion is a heating and a/c mecanic.I am now in the office portion of the buisness but still remember how to trouble shoot and diagnose problem's
I wish we had spell check I am realley having problems spelling tonight


[Modified by Ih2lose, 1:42 AM 9/3/2002]


[Modified by Ih2lose, 9:33 PM 9/3/2002]

Tom/99

:cool: idea!

pittsaj

Ih2lose
Or anyone else,

Have you tried the other R-12 replacements..
FR-12 and Freeze-12
My understanding is that they are very close to original R-12 and don't require oil change or purge.
Operating temps and pressure's are very close as well.
In fact, some ad's indicate you can top off a low R-12 charge without purging out the old R-12 ???

Any comments?

Tony

Ih2lose

QUOTE]Ih2lose
Or anyone else,

Have you tried the other R-12 replacements..
FR-12 and Freeze-12
My understanding is that they are very close to original R-12 and don't require oil change or purge.
Operating temps and pressure's are very close as well.
In fact, some ad's indicate you can top off a low R-12 charge without purging out the old R-12 ???

Any comments?

Tony[/QUOTE]
I had a major problem with the propane based refrigerent and have not used anything else besides the R134A it is a safe and stable gas.one of the problems with blending these gas's is you knever know what you have and thats why I always recover whats in it and then start from square one.I have a freind that was explaining the (freeze cool gas ) I will try and speak to him to see what he has heard of it

tuxedo

I would like to hear any comments on freeze 12. It seems a few car owners I know use this stuff and are happy with it. I believe the cost is affordable buit it is not as cold as the old freon gas.

Kid_Again

...a VERY interesting thread since i'm learning the do's and don'ts of recharging an original R134 system with R134...i'll have to continue this later but i would like to give my prespective on the phosgene issue......

....chlorinated hydrocarbons such as "freon" will form small amounts of poisonous materials at extremely high temperatures but that was not, frankly, the problem you ran into - please remember that "freon" is "halon" which is used to extinguish fires in closed environments...

...from the description in this thread of the sickness encountered when using "freon", it appears to be oxygen deprivation - you have to remember that "freon" is heavier than air, hence the real reason why computer rooms are evacuated immediately upon the discharge of halon - asphyxiation

Ih2lose

NO YOU ARE INCORRECT KID AGAIN and it is very important that it is understood that R22 & R12 BECOMES A POISONIUS GAS called fosgine WHEN EXSPOSED TO A FLAME as I allready stated
Most refregerant gas's are not explosive BUT they are poisonous when exsposed to a FLAME creating a gas called fosgine (like the old mustard gas)
As you all know from my history with the forum I do not argue with fellow members but this I am sure of

Kid_Again

....i will be happy to admit i am wrong if you provide a reference, rather than an anecdote...btw, you can't spell - it is phosgene, carbonyl chloride, an extremely poisonous gas at ordinary temperatures; it is an insidious gas, since it is not immediately irritating, even when fatal concentrations are inhaled (stedman's medical dictionary, 26th ed.)

...in plain english, you experience the irritation later, which caused the initial confusion in the trenches because the soldiers experienced delayed symptoms.........the description in this thread suggests an immediate effect....i never argued that phosgene could not be produced during combustion of chlorinated hydrocarbons (please re-read the post, which has not been edited) , you just stand a worse chance of dying in your car than from any "nerve gas" generated by a refrigerant...


...i respect your opinion, but, i love to argue, especially with someone who has the "caps lock" on

[


[Modified by Kid_Again, 6:57 PM 9/4/2002]

Viet Nam Vett

Quote*
----------------------------------------------------------------------------------------------

...i respect your opinion, but, i love to argue, especially with someone who has the "caps lock" on

----------------------------------------------------------------------------------------------


...............Kid_Again........COOL.... ... :cool:

Ih2lose

I just have to say I will not argue and do applogize for using cap locks I do also have to say I am here to help every one and anybody I can,and saftey issue are always a concern.
I honestly start the day with a goal to positiveley effect somebody during the day every day for the rest of my life.I am sure anybody who I have met personally will attest to that
I am certified in refregerant handeling all classes since 1991 prior to all the laws going into effect.I do not have any refrence books at home but tomorrow at work I will rumage thru our class room and get some good hard fax's up here for you guys to digest or some links.
If this was a dispute over the type of a clutch to install,the proper color for a alternator bracket I never would have responded to your comments.But this I think is important.
I do aplogies for my spelling I am getting worse and worse.

ghostrider20

When I was about 8 we had a neighbor kid that threw a party and some of the teens were huffing freon and one of them died. So I think it is poisonus in its resting form.

Mark

Ih2lose

I am posting this information to help others avoid a serious injury that I nearley died from not to prove anything else.

As quoted from the link below Decomposition can occur with any refrigerant when it gets hot enough (generally above 7000° F). Refrigerant can decompose in systems or containers exposed to fire or other extreme heat, electrical shorts (burnouts), or in refrigerant lines being soldered or brazed without being cleared first. Obviously, refrigerant containers or charged systems should never intentionally be exposed to a flame or torch.

When a refrigerant is decomposed or burned, the primary products formed are acids: Hydrochloric acid (HCI), if the refrigerant contains chlorine, and hydrofluoric acid (HF), if it contains fluorine. These products are certainly formed when hydrogen is present, such as from the breakdown of oil, water or if the refrigerant has hydrogen attached (like R-22 or R-134a). If oxygen also is present (from air or water), then it's possible to form carbon monoxide, carbon dioxide and various unsaturated carbonyl compounds -- the most notorious of which is phosgene.


http://www.refrigerants.com/refrsafe.htm
Asphyxiant

These are the poisonous gases. This class includes chlorine, phosgene and diphosgene. Chlorine inflicts damage by forming hydrochloric acid when coming in contact with moisture such as found in the lungs and eyes. It is lethal at a mix of 1:5000 (gas/air) whereas phosgene is deadly at 1:10,000 (gas/air) - twice as toxic! Diphosgene, first used by the Germans at Verdun on 22-Jun-1916, was deadlier still and could not be effectively filtered by standard issue gas masks

phosgene
Colorless, highly toxic gas used in chemical warfare as well as in industrial processes incl. the making of dyestuffs and polyurethane resins. Either alone or in combination with chlorine, it was used against troops in World War I. It smells like musty hay. Inhalation causes severe lung injury several hours after exposure. First prepared in 1811, it is manufactured by the reaction of carbon monoxide and chlorine in the presence of a catalyst. Gaseous phosgene is usually stored and transported as a liquid under pressure in steel cylinders or as a solution in toluene. Mixed with water, it forms carbon dioxide and hydrochloric acid.


[Modified by Ih2lose, 12:08 AM 9/5/2002]


[Modified by Ih2lose, 12:11 AM 9/5/2002]

pittsaj

I don't want to kill anyone,
I just want to charge my stinking AC unit.. :lol:

I promise,
I won't get it anywhere near Fire
I don't even smoke
Trust me!!

Tony

Kid_Again

Ih2lose...an excellent, excellent reply...perhaps now one can argue about data.......your facts reconfirm my recollection that HIGH temperature combustion ( i think you will find that issue a qualifier in your documentation because the end products of any combustion process are dependent on the amounts/ratios of fuel, oxidant and amount of energy added) of chloroflurocarbons (that is, R-12, NOT R-134a, which is lacking the highly reactive chlorine molecule, imparting different pressure/temperature curves and less atmospheric "ozone depletion" and is a straight fluorocarbon)...are produced PRECISELY in the rank order amounts you note - carbon monoxide, carbon dioxide and then the unsaturated carbonyl compounds (only one of which is phosgene but none of them are really a "day at the beach")......

...so, take a logical look at your own data and you will see that based on the relative amounts of the poisons generated, you are far more likely to become hypoxic (lack of oxygen and it's associated symptoms of deep breathing, drooling, cold, clammy, blue skin, decreasing brain function, then fatality due to all aspects of asphyxiation) because of the CO and CO2 and the heavier-than-air aspects of "freon" itself....all that is said with your well-placed point that even minute amounts of phosgene can be fatal - a very good caution for any rookie......

ghostrider20...you are absolutely correct in your statement that "freon" is poisonous - but remember, in it's native state, the immediate concern is the ability to displace air so the kids really died of asphyxiation because the lungs filled up with pure "freon"..if they used R-12, the chlorine atom caused a hell of a lot of irritation, if any newer fluorocarbon refrigerant, starightforward lack of oxygen, coma, death...not a pleasant way to go, at all

...now that we've dispensed with this episode of "Ask Mr. Wizard"....i'm in the process of saying to hell with the hearsay, i'm gonna go buy me one of those ASE textbooks on automotive air conditioning theory and practice and try to get comfortable with a good 3rd party reference (i know that you are a professional and know your stuff but i need REFERENCES)......

.......so, here's my question - i read in one of the hot rod mags (not really the same level as the Journal of Quantum Mechanics) that in retrofitting R12->R134a that the R-12 by-product aluminum chloride will react with the new refrigerant's PAG oil (no other explanation) and then they say you should blow out the system with a "solvent" before filling with R-134a.....W-T-F? (hey forum, you can't censor everything, you know!)...what is the deal here?....which "solvent" are they referring to and will that purge also remove the aluminum chloride????

thanks


[Modified by Kid_Again, 8:35 AM 9/5/2002]

Silver65

I intend to convert my '65 over, also. However, the mechanics I've asked to drain & flush the system before I do are all across the board as far as how much it would cost, and what needs to be done - i.e. change all the hoses out (to avoid "black death" of the hoses that have been saturated with R12 mineral oil), etc. :rolleyes: Is this really necessary (read: :bs ), or can I just change out the o-rings, flush the system, and recharde with the 134?