aaronz28

so - non corvette que -

my suburban has an R12 ac system still on it - and is fully charged with cans I had in my garage -
after a month of solid work - i believe the orafice is clogged - can I evac the system, replace the oriface and evac core and recharge with the reclaimed R12? or do i have to use fresh stuff?

Anyone know?

Powershift

You can remove the R12 and then later re-install the same R12. It does not go bad. BUT.........to do this correctly you need a means to reclaim/recover this R12 without introducing air into the mix and also temporary storage. Some folks have bought an old ac reclamation machine that still works from Ebay or CraigsList and use it. Previous CF C2 Tech Contributor and friend 62Jeff did just that. His story is in the FAQ Section and/or the archives. Probably 5 years or so ago.

Larry

EDIT: Recovery and reclamation is the only government approved way to deal with R12......but car owners and hobbysts are exempt from this practice. But if you apply for an get a EPA Refrigeration Certification (to legally buy refrigerants etc) and work for profit you MUST recover and reclaim or face possible $$$$$$$$$$$$$$$$$$$$$$$$ fines that can bankrupt mere mortals.

GTOguy

What Powershift said. Reclaimed refrigerant is re-used all the time in the industry. The evacuation equipment will keep it clean and contaminant free. Be sure to evacuate the system for enough time with a vacuum pump before recharging. No worries. Funny how R-12 and now-obsolete-ish R-134 are about the same price now!

DansYellow66

Without trying to dig up an old reclaiming machine are there any shade tree - but workable means of reclaiming and storing R12 for re-use at home? I rebuilt the AC system in my 67 GTX about 13 years ago and filled it with R12 and it's been good ever since. The independent shop guy who charged it for me is retired now. I would like to strip the car for repainting including the engine bay, but I'm holding off because of the R12 reclaim/recharge issue. I still have 5 cans of R12 but from memory I don't think that's enough to completely refill the system. And I'm afraid if I take it to a commercial shop I'll get charged for evacuation and then later get charged for the same freon to recharge it with.

Powershift

Dan:

The cost for you to build something will very likely exceed the cost of the R12 in the system. But it has been done. You could even try to use the cars compressor to pump the R12 into a recovery can after cleaning and evacuating the can. But these cans are themselves about $100 new. Plus you would need some kind of cold water or ice bath to help condense the R12 pumped from your system.

Five cans is enough for a recharge for most systems. You can buy R12 cans on Ebay for about $25/each. And you can sign a waiver to allow you to buy them as long as a licensed technician installs the refrigerant. Or get your own certification. I did, as well as MANY others. About 4 hours study and $50 or so.

Larry

DansYellow66

Thanks Larry - I have a couple car enthusiast friends in the Home HVAC business (self employed - small firm). I may talk to them and see if they have any thoughts/ideas on the subject as they have a lot of equipment and stuff around their shop.

Powershift

They should have the equipment needed............plus a recovery tank that you could probably borrow. Just empty this tank of any other refrigerant and pull a vacuum on it, and you are ready to go. You do not want to mix R12 and R22.

PS: This "mixing" of refrigerants happened about 7 years ago, where a CF guy bought a reclaimed 30 lb tank of supposedly R12. It had some R22 in it and we had a very hard time getting his system to work. I finally told him to get new R12 and then all was well.

Larry

63 340HP

They should be able to help.

Modern unmolested reclaim tanks have a check valve to prevent removal of the gas from the tank. The check valve needs to be removed, or use an older tank, for the recovered refrigerant. The tank should be dedicated for R12, more due to the residual mineral oil than a refrigerant concern.

In the days of refrigerant dinosaurs on large systems we would use a stationary compressor plumbed and piped with manifold gauge hose fittings so we could recover refrigerant into a cylinder, as opposed to venting it to atmosphere. Purge the hoses and piping with the refrigerant to eliminate as much air as possible before tightening down the fittings.

On small systems with expensive refrigerants (ultra low temp cascade systems and vacuum chambers) we would chill the recovery cylinder on ice or another refrigeration system to suppress the cylinder temperature and pressure and condense the refrigerant to help motivate transfer of as much refrigerant mass as possible. Dry Ice is cold enough to work with R12.

Avispa

i made that mistake, mixing R22 and R12, on an old Toyota wagon. R22 made the thing run so cold the evaporator would ice up. Definitely don't do that.

On the other hand, we can give the mixed gas to the Iranians. Let em do something with all their centrifuges other than making bomb grade uranium.