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recharging AC system

I'm doing the same on my TTA right now. When it comes to the A/C system, you really need to know what your doing with recovery, evacuating & properly charging the system. The TTA from the factory takes R-12, witch has been out of production since the mid 90's. You need a license to buy it at the store, if they even have any left & it is very expensive. Not to say you can't get a few cans off Craigslist or Ebay. BUT you need the tools/equipment to use it anyway.

Option 2: This is the route I might go my self. Freeze-12 has similar properties to R-12 for automotive use & is compatible with the R-12 and R-12 mineral based oil. Its been approved by the EPA as the only suitable R-12 replacement & from what I heard it blows colder than R-12 also. You can buy it online or at the store if they carry it, with out a license, its also a lot cheaper than R-12. You also need the tools/equipment to use it

Option 3: You can do a complete conversion to R-134a. Most people go this route because R134a is cheap, you can get it just about any where, no license required to buy it, its the only option the majority of people only know about & the majority if not all auto repair shops have the proper equipment to work on R134a A/C systems.

Not many repair shops have R12 equipment anymore & if they do, their usually sitting in the corner with cob webs & dry cracked service hoses, cause there not getting used anymore.

R-12 & R134a are NOT compatible with each other. R134a operates at a lot higher pressure than R-12, so the amount of R134a in the R-12 system needs to be less than the R-12 spec. Sorry, to ramble on but to answer your question They do make Freeze-12 and R134a charge kits, but either way, you really need to know what your doing or major damage can occur to your a/c system and get expensive very fast. Hope that helps!!!
 
I also need to do the same to 833....I have been wondering if i should even try and use the 30lb bottle of R12 i stashed in the garage 10 years ago...or not :)
 
I still have R12 in my TTA and it's blown ice cold air since the day I got it home. I'm actually surprised.

The main thing you have to keep in mind with R12 and R134a is that R12 you could kinda guess how much it needed to fill it and if it wasn't cold you could always add a little more till it got cold. R134a the mix of freon and gas has to be PERFECT. If it's not it will blow hot. You can't just "add some" to make R134a colder. So take the car to a place with the proper machines to make sure the mix is right. And like the guys said you can't mix them. So you have to stay with 12 or take it somewhere they can convert it for you. I have R134a in my 87 GN and it blows ice cubes. So if someone says R12 is colder then R134a they just never had the 134 done properly. They both can blow just as cold as each other.
 
I have R134a in my 87 GN and it blows ice cubes. So if someone says R12 is colder then R134a they just never had the 134 done properly. They both can blow just as cold as each other.[/QUOTE]

R-12 does blow colder than R134a, it has lighter properties than R134a & operates a lower pressures. R134a requires higher pressures to equal the same temp as R-12 would at lower pressures, thats why if you put R134a in a R-12 system, it has to be a specific percentage less than the R-12 system spec. Thats were it gets tricky, it needs to be near perfect & hopefully that repair shop that did the conversion correctly, witch it sounds like they did. I'm just saying theirs a lot more to a R134a conversion than most people know.

Example: Usually the proper R-12 to R134a conversion involves removing the compressor & manually draining in completely (it may even need to be replaced depending on condition), replace all system rubber hoses & o-rings, flushing all the metal lines, evaporator, condenser, installing a new receiver/dryer and expansion valve or orffice tube (depends on what system you have) and replacing the overlooked high/low side schrader valves & pressure switch. Installing the new updated service ports also.
(let me know if I'm missing anything)

ITS VERY IMPORTANT THAT ALL R-12 mineral based oil is removed from the system since R134a synthetic PAG oil is not compatible with it. If any mineral oil is left in the system it can hender/and or ruin the a/c performance and greatly shorten the compressor life & blow out o-rings like no tomarrow (hence the higher R134a pressures the R-12 system is not designed for).

There are a lot of shops that have inexperienced mechanics or mechanics that just do what their told against better judgement, do conversions and all they do is recover what's ever left in the system, install the new "service port conversion adaptors R-12 to R134a" and charge the system up. It will blow cold, but the a/c system will be short lived & be on borrowed time. :explosion:

R134a in a vehicle designed for R134a will blow very, cold equal to R-12!!!
R134a in a vehicle designed for R-12 will blow cold, but not as good as what the system was designed for R-12.
Freeze-12 in a vehicle designed for R-12 should blow even colder than R-12 (its lighter than R-12) and is compatible with R-12 and oil.
 
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Just to give you and idea on price. Where I work we still service r12 as well as 134a systems. We charge $48 a pound for r12 and $12 a pound for 134a thats used during repairs.
 
Rodimus_Prime said:
so where can i take it?
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Take it to a certified mechanic who has experiance on working with a/c systems. Or take it to a reputable repair shop who knows what their doing with a/c systems. You have a few options on what route your going to choose, just do your home work on witch route will best serve your needs & budget.
 
Just my .2cents, on the R134a conversion from R-12:

1.) If your restoring the car (any make/model with an R-12 system) starting from scratch with everything new. Do the R134a conversion.

2.) If you plan on selling the car in the very near future & don't want to put the money into it, sell it before it snow balls into something more. Do the R134a conversion.

3.) If you plan on keeping the car for a long time to come. For the proper long term fix. Use what this system is designed for, R-12. Freeze-12 also falls under this, as its compatible with the R-12 system, more available than R-12 & cheaper to buy.
 
Be careful with Freeze 12. It has propane in it and is dangerous if not used properly. Lots of HVAC guys will not work with it.

85% of the required r12 charge for the 134 charge has worked well for me on a few vehicles. Don't forget oil takes up system volume so make sure sure to use the correct capacity.
 
1tufam said:
Be careful with Freeze 12. It has propane in it and is dangerous if not used properly. Lots of HVAC guys will not work with it.

Its not propane, it contains "Difluoromonochloroethane" similar family i guess. I've been working in the automotive field since 97" and thats the first I ever heard of techs not wanting to work with Freeze-12. Check out this link for more info.

http://www.freeze12.com/
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I plan on keeping the car for a while, i could care less about originality of the ac system, I dont want to have to replace parts or spend a ton on it, i want something easily serviceable, i hardly if ever use the ac but if i do, i want it to work right

I dont feel like bothering with it myself could like pep boys do this or do i have to go to a dealer?
 
If you are going to use R-12 It takes 2.25 lbs. So if it costs $48 per lb just the R-12 would run you about $108 not including tax. Plus the labor to put it in, depending on labor rate, would be probably about another $100. Give or take. The conversion kit I believe the price just went up on these. The ones at work wereabout $25 last year, but are now about $48. That just includes the new fittings and two bottles of oil. As far as where to take it? Call around. I am not sure if Pep Boys has the equipment, and not every place still has R-12. In fact, I just found a 30lb bottle of it at work but I am not sure if we still have the equipment to use with it. Either way, I would love to get my hands on the bottle.
 
i just want to take it someplace local and have them deal with it, i have no interest in wasting my time on it trying to do something i know nothing about
 
If the G.M dealer has been around for a while, they should have the equipment to do the job right. The older techs if any their, worked on these cars or f-bodys in general, back when they were new and are factory trained. Pep-boys, who knows what kind of mechanic will be touching your car, they most likley never seen a TTA or know what one is.

Read my previos post, a $25+ dollar conversion is exactlly that, new fittings w/PAG oil (stay away from that, if your going to keep your car long term) but its your car,time & money & you have to do whats best for you . Choose wisely & good luck
 
Two out of five technicians also did not know the service fittings on an A/C system must be changed if the system is converted from R12 to R134a or anything else. And three out of five technicians did not know mixing R12 and R134a could cause problems.

Well thats pretty depressing
 
Rodimus_Prime said:
Two out of five technicians also did not know the service fittings on an A/C system must be changed if the system is converted from R12 to R134a or anything else. And three out of five technicians did not know mixing R12 and R134a could cause problems.

Well thats pretty depressing
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Yup, its kinda scary huh?
 
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