I have read that R406 freon is a direct replacement for
R12 freon in older AC systems.
Is there some fellow C3 member who can dial the rest of
us in on this stuff?
Is this something we can purchase,and install ourselves?
Steve

Well, Ill try to answer some of your questions based on what I know.

R406 is an approved refrigerant by the EPA. This refrigerant requires barrier hoses in order to prevent leakage through the hoses. This refrigerant requires its own unique fittings, lables, and compressor shut off switch to be legal. Note this refrigerant is NOT approved by vehicle manufactures. A dedicate recycling/recharging machine is required for this refrigerant.

As for it being a drop in replacement, there is no such thing yet. R-12 has its own unique properties and cannot be duplicated with other types of refrigerant.

If possible, stay with R12 if your pocket is deeeep enough. I prefer to go with the R-134a because its less harmful to the environment and saves you money.

Also, I dont recommend people with little or no experience to handle refrigerants without proper training and license.

-Emerson, ASE certified Tech.

Sources: Automotive Heating and Air Conditioning by Boyce Dwiggins. ISBN 0-7668-0934-X

Did a Google search on r406 freon and came up with autofrost.com & yarchive.net/ac/r406a.html (among others). Some interesting info.

Marc

I will echo the recommendation to stay with 12 if you can afford it, otherwise convert to 134A. All the 400 series refrigerants are blends that may fractionate with leaks in the system. 12 is certainly the best choice because of the relatively high underhood temperatures of our C3's compared to most other vehicles.

I am not familar with r406, but would avoid it like the plague unless I knew more about it. Many subsitute freons are a blend of butane and propane. They work great, but can incinerate your car in an accident. Some are very posionous. Not good if it leaks inside the car. Many states have outlawed subsitutes due to these problems, many have not. Some is sold illegally.

R12 and R134 are the only things that can safely be used. Switching from R12 to R134 will lose about 10% cooling capacity, unless modifications are made. R134 is also a smaller particle and will leak from R12 hoses and seals. Sometimes residue will seal lines and hold it in the system. None of our C3's have rubber components designed to hold R134, but it may work. IF the seals, hoses, and gaskets are changed, it will work. R12 is most likely to stay in the system. It's cheaper than a full conversion to R134.

Ken Styer

Not to go against the grain here... BUT I did a R134A conversion kit and it worked EXCELLENT! I did this in my old Trans am. It cost me 50$ for the retro kit at Pep Boys which consisted of some different valves, the freon, and a hose to charge it with. It lasted over two years before I sold the vehicle and was still blowing ICE cold when I sold it. I've never heard of the refrigerant you are asking about, but for me the 134 worked better than the 112 did. I had it charged in Mexico with 112, found a leak, repaired it, then did the 134A and wished I had never gone south in the first place. Hope this helps you.

The R134 does work well. The slight loss is usually not noticable. I replaced the R12 with R134 in my daily driver. The wife's mini van still has R12. The only reason I may use R12 in my C3 is the fact the system is old, and it may not leak as much with the R12.

Ken Styer