A/C refrigerant 1991 Roadster

"Eric Baber" wrote in news: snipped-for-privacy@individual.net:

A 1991 will use the banned refrigerant (R12), it can be converted to use the later type of refrigerant (134a) by replacing all the oil in the system since the oil in your system isn't compatible with the later refrigerant. Removing and replacing the oil almost certainly requires replacement of the compressor and the receiver/drier (or accumulator, if that's what Mazda uses) along with maybe a couple of other minor parts which is costly. There might be a very slight reduction in cooling with the later refrigerant but it probably won't be noticeable.

Oh, the fittings for charging the system may also require replacement as 134a uses different ones. A knowledgeable mechanic will be able to get around that problem, though...

If you want air conditioning you really have no choice unless you can find a shop that does have a stock of R12. I don't know the law there but here if a shop has it they are allowed to use it, the ban is on manufacturing the stuff AFAIK.

You will also pay a large fortune for R12 if you can find it.

If anyone here is from Raleigh, NC.

I know a shop that will recharge R12. Yes it is expensive, but IMO my '93 Ranger with R12 is colder than my wife's 2004 Toyota R134A.

Thanks for the information, anyone. Looks like I'll be putting my a/c out to farm; it's not really worth converting it to the new refrigerant.

Thanks

Eric

"Everyone", even.

Eric

Update: I've just phoned a few companies and have found one that uses a "drop in" refrigerant, RS-24

Eric

"Eric Baber" wrote in news: snipped-for-privacy@individual.net:

I don't know anyone who's tried it, let us know if it works!

Correct but misleading. It's pretty much impossible to remove the oil from the receiver/drier, it needs to be replaced. The compressor can be drained but that almost always requires that it be removed. If you try and convert w/o removing *all* the old oil you'll have some problems a couple of years down the road with leaking seals, etc.

As for the fittings, they don't need to be changed IF you have a reasonably savvy AC guy, he can use a gauge set with hoses that will fit the old fittings to charge with R134a.

Will do. I did some more research on the net and found various companies in the UK that offer a recharging service with RS-24 for old R12 units, and one forum on which someone said they'd had it done and were happy with it, so it appears to be legit. I've booked the local guy for tomorrow to do the recharge so will let you know how it goes. Supposedly using anything but the manufacturer's recommended materials, i.e. R12, will invalidate any component or manufacturer's warranties, but given that only cars built before 1992 or so will be using R12 I'd say this is an academic argument.

In case anyone is interested, some good references/examples I found are

Eric

Right, the guy has just been and gone and has recharged my Roadster's a/c with RS-24 refrigerant. The process was as described at

"Eric Baber" wrote in news: snipped-for-privacy@individual.net:

Great, glad it works. It's nice to know there is a replacement for R12.

Eric, please keep up posted on your experiences with the new fluid. Although

Jeroen Feelders MX-5 Club of the Netherlands

"Eric Baber" schreef in bericht news: snipped-for-privacy@individual.net... | Right, the guy has just been and gone and has recharged my Roadster's a/c | with RS-24 refrigerant. The process was as described at |

OK, some more info now that I've been driving with the new refrigerant for a week or so.

In general, it "feels" nearly - but not quite - as cold as the original R12. As I said I never measured the temperature with the R12 before it ran out, but on several occasions I'd be driving with the top up and the air-con on 1 or 2 and turned down all the way; after a while I'd get too cold and would have to turn it less cold. With the new refrigerant that hasn't happened; I can drive pretty much as long as I like with it on 1 and turned down all the way without getting too cold. Then again we're having a particularly hot summer so perhaps the outside temperature is just hotter than in the past, and the a/c is having to work harder.

Some temperatures I measured today:

Outside temperature: 31 (centigrade, as all the other temps here) Temperature of air coming out of blower, on 2 and turned down all the way:

1. It maintains this when turning the blower down to 1 once it's got down to that temperature.

An ambient temperature of 31 isn't all that hot this year - we've had 35/36, but on those occasions I haven't had a thermometer to hand (funnily enough I don't carry one around with me wherever I go :-)) I might get around to measuring the cockpit temperature at an outside temp of 35, then again I might not. (And yes yes, I know I know - 35 probably isn't all that hot for some of you, but for the UK it's really something).

Hope that's useful!

Eric