I have three pre-1993 cars with aircon systems which use - as originally installed - R12 (Freon) refrigerant. One car has been in storage for some years and the a/c has not been regularly run. I fear therefore that it will at least need a check and top-up. And eventually, so will the other two.
BUT... R12 is apparently no longer available, even to maintain existing systems. I have heard of two options: top up with a "drop-in" R12 substitute, or empty the entire system and replace seals, pipes and maybe compressor then refill with R134a (which is not compatible with R12 and is itself rumoured to be due for phasing out soon).
Neither option seems attractive. Compatible substitutes are said to be unreliable "Band-Aid" solutions, and changeover to R134a is expensive. This seems bizarre: it is surely less wasteful of resources and more environmentally friendly to keep existing R12 systems intact and running well than to have to empty them, dispose of the R12, fit new parts and use alternative (but probably equally environmentally-unfriendly) refrigerant fluids.
Although R12 is not now used in new cars in the EU or in the US, it is apparently still possible and legal in the US to obtain and use recycled/recovered R12 to keep existing R12 systems topped up. Is this possible in UK? (and if not why not?).
Any comments or advice?
br1anstorm
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Car manufacturers recommend the use of only r134a as a substitute for r12.There are loads of "drop in" replacement gases that will do the job of r12 but most of them consist of a very high percentage of 134a, so you might as well use the "real thing".Older cars can successfully be retrofitted to 134a as long as the integrity of the system is good; Pipework,condenser ,cooling fans both engine driven and electric must be up to the job.I would suggest you use the services of a competent car a/c service engineer who will advise you as reqd,a conversion to 134a may not be as expensive as you think.hth
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Exactly a year ago I paid just £50 (+VAT) on top of the normal regassing bill for an R134a conversion kit to be installed in my 1990 MB. It's an Airco Retro-Pro, of US origin, I think. Seems to work fine, and the installer had every confidence in it, having installed plenty with no reported problems.
The accompanying document says "If the system is running well, then you need only to add Retro-Pro as described below. Depending on the age and condition of the system, it may be necessary to change parts such as the filter drier, expansion valve and any non-barrier rubber hoses." None of that was required in my case.
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There is a specialist oil from America which allows conversion to R134 from R12 with no ill effects & has worked satisfactorly for years or you can use an isceon R49 gas. You can buy retro fit valves which will allow conversion of the ports for R134 connections
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Stay with R12 if possible.
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Stay with R12 if possible.
That's what I'd like to do. Seems the common-sense way. But how can I, if I can't top up with genuine R12?
I know R134a conversion is recommended by manufacturers. But R134a molecules are I'm told smaller than R12, so there's greater risk of leaks and compressor malfunction unless most of system fittings are replaced. And while it's true that both R12 and R134a systems also need a small amount of mineral oil as well as a lubricant, the oils used also differ. I've been told you can't mix R12 and R134a, nor mix the oils used with each (a bit like not mixing regular and synthetic brake fluid without purging and cleaning the circuits...).
Bottom line remains... how and where might it be possible to get small top-up quantity of R12?
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"Bottom line remains... how and where might it be possible to get small top-up quantity of R12"
You can't. Only the MOD have any, and it's illegal to use outside of military applications.
Do a proper conversion, using R134a and an ester oil, as recommended by most of the manufacturers. Any other replacement refrigerant uses R134a as the major component anyway.
You'll need a new filter/drier that's compatible with R134 (but you'll also need that with any replacement, although the suppliers of these replacements won't tell you that), try and flush out any of the old oil, add the new oil, change the service ports, and refill with 80% of the old R12 capacity as a start point. If you then have any further problems, which is very likely with an old system, then you can go anywhere for R134a, and not be tied to some magic replacement that no-one has and no-one will want to recover.
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