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R12,r134a, freeze 12? Air Conditioning Question/Options

I just got a 1992 Ford Tempo GL 4 door sedan with 83,000 miles on it for $850. I spent $160 on an alignment and a new caitylic converter and basic tune up. Now my problem is the air conditioning system is the old r12. I don’t want so spend a million dollars to retrofit it. I have heard that you can use freeze 12 and keep the same oil in the system. I will still have to have someone do it though as I have no idea how to. I was told with r134a you have to liquid flush and with freeze 12 you just have to fit it and its cheaper and cools better.

What do you think I should do? Can I do an r134a myself? I know there are tools at auto zone to borrrow, but If i get someone to do it , I don’t want to be ripped off.

It’s generally not a good idea for a novice to mess with A/C work because it can be frustrating if you have to keep backtracking to figure out where you went wrong and it can also be a bit dangerous. Refrigerant can cause frostbitten fingers quickly and blindness instantly if something goes wrong.

The car is 18 years old and the system likely has leaks that must be repaired before a permanent solution can ever be found. The best way of inspecting for leaks is by pulling a vacuum and seeing if it holds.

R134 is what I always use. It’s seldom ever a problem and will get just as cold as anything on the market. It’s also possible to do a backyard conversion by doing nothing more than adding some PAG or Ester oil along with the 134 and calling it good. I did this on my old SAAB and Mercury about 10 years ago and both cars would darned near freeze a side of beef on a 100 degree day.

To do this in even a half proper manner you really need a full set of gauges, a vacuum pump, and it’s preferred that you spend a bit of time reading up on A/C theory in advance.
And always keep one thing in mind if you proceed with this. You never, ever, open the high side gauge with the refrigerant can tap open. This is where the frostbitten fingers/permanent blindness thing comes in.

So how much will a mechanic charge me to retrofit my system to r134a? What about the freeze 12 method, of just removing the r12 and then keeping the r12 oil like it says getting fittings, and then charging?

I heard mechanics use to charge boatloads to retrofit, is that still true?

freeze 12 is made up of mostly R-134a, and R-134a will start phase out in 2011.

Edit: The phase out starting in 2011 is for Europe, but its safe to say it will not be long before the U.S. follows

I agree with using R134a. I have used this for years when retro-fitting and never had a problem. Note: R134a is being phased out. German engineers have discovered a new refrigerant that is harmless to the environment. It’s called…believe it or not…nitrogen. They are working right now to to work out the bugs but it seems like it works just fine.

Freeze 12 will likely work well in your situation. My history with Freeze 12 has been to install Freeze 12 in a questionable older system to determine what works and what leaks. My old pickup has a leaking evaporator and I have been lazy the past 3 years and added 2 cans of the Freeze 12 every summer to keep it cool. It’s such a cheap and simple alternative to ripping out that evaporator. Maybe I’m lazy. I like to think I’m practical.

But how much will it cost me to retrofit? Are you saying instead to try and go find some r12? If I have a slow leak in my system at all I think they wont sell you r23 and I am not sure if you can fix a leak on an r12 system.

Please I need to know what to do here.

I have used Freeze-12 as a “make-up” charge in R12 systems. It works fine and with no problems. BUT. again BUT, if your system is EMPTY, you have a serious leak that MUST be located and repaired FIRST. Under the hood, find the A/C compressor, it’s belt driven. There will be two refrigerant lines, low and high pressure. The high pressure line will go the condenser in front of the radiator. The low pressure line, the return from the evaporator inside the passenger compartment will also lead to the compressor. Both lines have service fittings or ports that are closed by common shrader valves, the same type that are used in tire stems. There are usually dust caps over the fittings. With the engine off, remove one of the caps and using a blunt probe, momentarily depress the valve. (wear safety goggles). Hopefully, Freon gas under pressure should escape. That means a quick boost with Freeze-12 might work. If you detect no pressure in the system, repairs will be necessary before any refrigerant can be installed. At that point, you might as well convert to R134a…Enter “R12” in the search window of this board for a complete list of former discussions on this subject…

I used to have an '88 Honda Accord that ran R-12. At some point it sprung a refrigerant leak and needed a recharge. I got a couple cans of Freeze-12 and it worked just fine, blew real nice and cold. That’s probably the most economical thing to do for now.

Any leak on an A/C system can be repaired and it’s impossible to say how much a retrofit will cost. Too much depends on the shop procedures for doing this, the location where you live (which affects shop rates, etc.), markup on parts/supplies, etc.
Wild guessing from a 100 bucks for a charge and pray situation up to a couple or three hundred dollars.

Your best option is to call a few shops in your area and get a ballpark quote, but keep in mind the cost could vary quite a bit depending on what is done.
The one thing that should be done is to have a vacuum pulled on the system and determine if it’s leaking. If it leaks (quite likely) then it’s up to you to determine how how much further (a.k.a., money) you want to go with diagnosing and repairing any leaks.

A/C repair can get expensive but just because it is expensive does not mean you’re getting ripped off.

I strongly recommend against depressing the high-side Schrader valve, particularly when the OP doesn’t have experience messing with A/C systems. If this must be done, try it on the low-side valve (the larger of the two lines running to the compressor).

I suppose it goes without saying that venting refrigerant into the atmosphere is a violation of federal law…

In a non-functioning system, high and low side pressure, if any, will be the same, around 90-100 psi.

Ok so I should say that the system is occasionally not cooling,it worked last night, but not the day before for about 5 hours, then came back on again. I just got this car

I have decided to get freezer 12 for now. I went into autozone to see about renting tools , they rent a vacuum system for $200 and the gauges for $100 but you get your momey back when you return the items. The retrofit kit has the fittings and the coolant plus a gage for $39.99 but still I would be taking chances here. I spoke with a friend at O’Riely auto parts and he said to go to car quest as they sell the freezer 12 here. I was told by 3 different mechanics that as long as your system does not leak it is ok to top it off with freezer 12.

Looks like You cannot mix r12 and freeze 12 legally, so Now I don’t see how it would be more cost effective to retrofit to freeze 12 vs 134a (even though europe wants to fizzle out r134a). However lots of testimonials say freeze 12 works better on older systems because it has pressure near the same as r12 and cools the system better when idle or moving slow in city traffic.

If your A/C works fine sometimes, and other times not, it may not be a problem with the refrigerant level. You should have the cars A/C checked by a Automotive shop that specializes in A/C repair. A/C repair can be dangerous, and cause harm to you, and the cars A/C

Ok great, what do they usually charge just to take a look? I would still have to find someone who is licenced to look at r12 systems

“I spent $160 on an alignment and new caitylic converter and a basic tune up.”


Who gets a new catalytic, or “caiylic,” converter, not to mention an alignment and a “basic tune up” for $160?

The R12/R134/Freeze12 question is not this person’s biggest problem.

Um , considering my converter was old (it was rusty and had rocks in it and needed to be replaced) and the alignment was simply because the wheel was turning to the right , the car was pulling, all those repairs are done now. The car is running smooth now so my problem is just the AC

The legal-illegal issue aside, (nobody has gone to jail), if you just want to top it off quickly and easily, use the Freeze-12. The problem is, you will now have two mixed refrigerants and NO licensed shop will TOUCH your system because they must protect the purity of the gasses in their freon recycling machine. Later on, should you desire a professional repair / recharge, you will have to DUMP your mixed refrigerant by removing the schrader valves. Then, with no freon to reclaim, they will do their thing. Back when there were MANY R-12 systems still on the road, they worried more about this issue. But the fact remains. Sooner or later it is ALL released into the atmosphere anyway. But since they would like to reclaim and SELL your R-12, they don’t want it “contaminated” with Freeze 12…That’s why mixing refrigerants is “illegal”…