AC R12 Freon Substitute

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I have a couple of old cars that use R12 freon. I was able to buy this replacement freon called 'freeze 12' a few years ago, but found out that it has been discontinued now. Anyone knows if there is another substitute we can use in the R12 AC system? It appears that even the DIY R134 freon (small size can) is outlawed in California.

Please do let me know if you have some 'freeze 12' for sale. ;-)
 
R12a as stated in the article is a hydrocarbon based refrigerant. There are quite a few brands up here and Canada, and is readily available. State side, you might want to try eBay? Freeze 12, Duracool, RedTek, it's all the same stuff.
 
it is kinda scary... .would this stuff explode? I see that it requires converting to r134a first as the fittings are different than R12?
 
A few years ago I went ahead and paid the $20 to take the training/testing to get certified. This allowed me to purchase R12 for use with older vehicles I like to keep 100% stock. A few days later I was mailed my certification card, which I then used to purchase R12 online. It's still manufactured in large quantities and used overseas. I find that R12 is cheapest when purchased during winter. Summer costs skyrocket. All my R12 systems hold a charge much much longer than any of the R134A systems. For example, I charged my '87 RX7 once out of more than a decade of ownership.

Here is the company I used:
http://epatest.com/609/
 
It is easy to convert to 134A which is what I do at my shop whenever a car comes in requiring repairs to R12 system. I have not been able to find R12 for sometime and believe freeze 12 is not quit the same. The adapters are available to change the fittings at most auto parts stores. The 134 is inexpensive I pay less than $3.00 a pound when buying 30lb cylinders.
 
but the upgrade kit at any parts store its contents are 2 new fittings that go over the valve stem and a tube that connects to the small cans. 29 bucks I think it comes with 2 cans but I have found 2.5 cans fill the NSX.

the best way to know if you have enough is if the driverside is blowing ice cold.

when filling lets say an empty system on the NSX as you filling it put your hand over the passengerside vents when it gets cold you know your half way done.
when the driverside gets ice cold your full and stop.

if the driverside is warm and the pssengerside is ice cold your only half full. keep that in mind.
 
I just stocked up 30lb can and 8 12oz cans

IMG_20130502_164211_983.jpg
 
Does the R134 work well with the R12 system seals? As for conversion, do I just screw on the R134 fitting over the R12's? Do I need to evacuate all the R12 out of the system or it is ok to mix?

Can I still buy the R134 freon over the counter? Thx.

It is easy to convert to 134A which is what I do at my shop whenever a car comes in requiring repairs to R12 system. I have not been able to find R12 for sometime and believe freeze 12 is not quit the same. The adapters are available to change the fittings at most auto parts stores. The 134 is inexpensive I pay less than $3.00 a pound when buying 30lb cylinders.
 
The NSX system works fine after converting to R-134a using Acura's conversion kit for doing so. I did that with mine!
 
I always keep several cans of R12 on hand. I recently had my evap replaced and handed my tech some R12. I'd suggest if your going to convert to 134, at least replace as many orings as you can with the green orings. They are much more durable and designed for 134. R134 does operate at a higher head pressure than R12. Personally I'll stick with 12 as long as I can get it.
 
You would need to have someone recover the old r-12 from your car. Then have the system evacuated before converting to R134

FYI- you can get some r-12 on ebay if you can't find any local


Bryan


Does the R134 work well with the R12 system seals? As for conversion, do I just screw on the R134 fitting over the R12's? Do I need to evacuate all the R12 out of the system or it is ok to mix?

Can I still buy the R134 freon over the counter? Thx.
 
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any parts store has the upgrade, and yes you just screw the new couplings on the old stems.

as for if the system still has some r12 in it, I have known people that put a wrag over the low pressure side, the one closest to the battery
and pressed down with a flat head screwdriver till no more sounds come out. but thats illegal and it hurts the ozone.
then they put the new caps on, and fill it and they were done is 20 minutes, vs drive to a random a/c shop pay them to remove the old r12 then drive home and finish the upgrade.
 
I googled it and it appears that it is the ester oil in the r12 that may cause problems. it may solidify when mixed with r134a. However, some people stated that the r134a conversion kits (Interdynamics EZ Chill R-12 to R-134a Recharge and Retrofit Kit) are compatible with the r12/ester oil. So please chime in...

Also, I was under the impression that the oil needs to be suck out by the machine?

any parts store has the upgrade, and yes you just screw the new couplings on the old stems.

as for if the system still has some r12 in it, I have known people that put a wrag over the low pressure side, the one closest to the battery
and pressed down with a flat head screwdriver till no more sounds come out. but thats illegal and it hurts the ozone.
then they put the new caps on, and fill it and they were done is 20 minutes, vs drive to a random a/c shop pay them to remove the old r12 then drive home and finish the upgrade.
 
any parts store has the upgrade, and yes you just screw the new couplings on the old stems.

as for if the system still has some r12 in it, I have known people that put a wrag over the low pressure side, the one closest to the battery
and pressed down with a flat head screwdriver till no more sounds come out. but thats illegal and it hurts the ozone.
then they put the new caps on, and fill it and they were done is 20 minutes, vs drive to a random a/c shop pay them to remove the old r12 then drive home and finish the upgrade.
A perfect example on how we all need to "up-grade" to save the environment. But first all that old dangerous R12 that was contained safely get released into the atmosphere! It needs to be contained or recovered to actually save the environment.
My neighbor is a refrigeration mechanic. He can get into a lot of trouble releasing R12 into the environment, but if it "leaks" out on its own, no issue. In my opinion, the R12 should only be removed when the car is scraped or there is a need to repair the system.

I have been lucky. My R12 in my 1991 still blows cold and hasn't been a problem. My backup is my neighbor. He has plenty of R12 on hand.
 
I'm not sure, but I helped my brother converted his R12 A/C to R134a in a Suburan, he uses to take his family camping, last summer. He chose to do it while I was out there for a visit. :confused: It was a much larger project than I or he thought it would be.
He needed to replace the compressor/clutch, the Receiver/Dryer (I suspect we may not have needed to replace it), an expansion valve, Conversion Kit (oil & new system valve stems), EPR Valve, and hoses because the fittings for the compressor were different sizes on the new one.
He had to run some stuff to clean out the system if I remember correctly. The R-12 residue would gunk things up he was told.

It was a bigger job than just changing some fittings, o-rings and coolant.

I believe he purchased some Freeze 12 on-line but then went with the 134a conversion.

But neither of us are mechanics. I do some DIY. This was more his project he figured he would rope me into, figuring if he had his big brother with a laptop to the Internet he could do anything :smile:

Good luck & keep us posted... I'm sure there are people who have been there, done this with their NSX here on prime.
 
FYI if someone finds you venting that r12 and films it or calls it in and has proof. They get a award of up to 10k and you get a fine of up to 25k. So be careful on the DIY stuff out in the open... Best to recover it, drain the oil and replace with the proper POE oil, change the drier and o rings. Then evacuate the system preferably to 500 micron vacuum. And recharge it with the proper amount of R134a.
The txv could be reused since 134a is the proper replacement for 12. But if you feel like replacing it go ahead. In some equipment the design of the valve has changed.
Hope this helps, I'm a HVAC tech not a auto tech thou.... But have worked on several auto ac systems.
 
FYI if someone finds you venting that r12 and films it or calls it in and has proof. They get a award of up to 10k and you get a fine of up to 25k. So be careful on the DIY stuff out in the open... Best to recover it, drain the oil and replace with the proper POE oil, change the drier and o rings. Then evacuate the system preferably to 500 micron vacuum. And recharge it with the proper amount of R134a.
The txv could be reused since 134a is the proper replacement for 12. But if you feel like replacing it go ahead. In some equipment the design of the valve has changed.

Good warning.. that is why they only want licensed people working on air conditioning systems. In my brothers case the R-12 was already long gone. It had a leak from a seal in the back of the compressor. Initially he thought he could replace the seals/o-rings.

Somewhere along in the process he decided after some research & talking with others his best option was to convert it over to R134a. It was quite a project as it had rear air and one of the valves was under the passenger dashboard and had to cut through some plastic case to get to it, etc. BUT he did save quite a bit of $$$ over what he was quoted by a shop to do it.
It took most of a Saturday..
 
Can I use Maxi Frig 12a in my 1991?
 
Thanks for the info. It's not that I'm too lazy; I just can't justify the cost to do it the right way!
 
Just some FYI notes:

1) R12a is hydrocarbon based, thus is more subjected to "explosions/fire"
2) If you system is leaking, you are probably low on oil as well. R12a oil is compatible with R12 oil
3) There should be a leak stop product that might seal any pin hole sized leaks
 
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