More air con questions: Gas?

TB2 · Post by **TB2** » Sat Jun 13, 2009 6:28 pm

I went to a citroen dealer yesterday asking how much it would cost for a professional to refurbish the air con on my BX. He didn't know but he asked a mechanic in the back and that guy said that the BX allegedly uses an old gas called R12 or something like that and that they don't do that anymore. Instead they have some R-100-and-something these days. He couldn't tell me someone who would do it either...

Is this true? Could it really be a problem? It might just be the Swiss once again disregarding slightly outdated technology....

Thanks guys and girls...

Regards,
Carl

Way2go · Post by **Way2go** » Sat Jun 13, 2009 7:14 pm

Yes, it is true. R12 is no longer allowed as it is an ozone layer attacking gas. R132a can be used but needs different oil and additives to protect the 'o' rings.
There is a mass of info on this subject if you search earlier posts in the forum, much of it by the late Alan Smith for who it was a favourite subject. Alan always advocated the replacement of the 'o' rings at the same time to green neoprene ones.
He also advocated a new compatible gas called Greenfreeze which was available in Australia but I never found a source in the UK.

Philip Chidlow · Post by **Philip Chidlow** » Sat Jun 13, 2009 7:17 pm

The system did use the now illegal CFC-type stuff R12. For a while RS24 was recommended, but the price of that went through the roof (and I don't even know if it's available now). An R134a conversion is possible (I had an R12 to R134a conversion done to my Toyota TownAce for about £90). Don't know of one done on a BX tho'. Anyone on here know of one?

TB2 · Post by **TB2** » Sun Jun 14, 2009 8:09 pm

Thanks, I'll see what I can do...

Post by **mat_fenwick** » Sun Jun 14, 2009 8:38 pm

I think Tom Sheppard converted his (now with DLM) to use R134a. I changed all the seals on mine when I fitted it to the green neoprene ones, ready to do the switch, but then I discovered the drop-in replacements such as RS24 were readily available (this was back in 2006). Still running on RS24, although the control unit may have a problem at the moment.

Vanny · Post by **Vanny** » Sun Jun 14, 2009 11:55 pm

Just to clarify a few things, R-12 isnt specifically illegal. It doesn't meet emisions standards for manufacturing, and it isn't legal to manufacture the R12 refrigerant within europe, and sales of refigerant made after the cut off date (i forget when but in the 90's i think) is illegal and has high penalties. As such you can still get R-12 refridgerant manufacutred before the cut off date. This only has an impact on Europe as well. The US and Gulf states still use R12 as it is a significantly better refridgerant than R132, or R1234yf or CO2. My understanding is that the best refridgerant is LPG but carries some hopefully obvious risks.

Also neoprene seals are naturally a yellowish colour, though they can be coloured to just about anything, so if your ineracting with a system that doesn't have green coloured seals that does not mean that it is R12. Symantics possibly, but there has been a lot of missleading information on this forum regarding HVAC systems.

R134 becomes obsolete in the near future (2012 i think), and the replacement is still being fought over (either R1234yf or CO2). If you want to know something about older systems you would do worse than contact a company called Autokool in Derby. They sell everything you need for DIY conversions and maintenance, and provide a wealth of support by email and phone. I have had dealing with them in the past and there support has been excellent.

I have a number of associates who work for a company that makes automotive HVAC units, and while i know relatively very little based on there teachings, what i do know is that the BX system is very simple, easy to work on and well within the limits of a competant DIYer.

TB2 · Post by **TB2** » Mon Jun 15, 2009 6:01 pm

I'm going to Poland in a few weeks, I wonder if they still refill R12. I'll ask a Polish friend. Or maybe I can do a conversion over there for cheap.

Thanks for all the infos Vanny!

velosolex50 · Post by **velosolex50** » Mon Jun 15, 2009 7:29 pm

I had my r12 bx system regassed with RS24 (I think) 2 years ago, without modification or oil change, and it is still ok. Not quite as cool as the original though

Vanny · Post by **Vanny** » Tue Jun 16, 2009 12:28 am

R12 in Poland? I'd say almost guaranteed, might have to have a hunt around for someone to do it, but if the system is still air tight then it shouldn't be too big a problem. It is still possible to obtain and use in the UK for research purposes, but that could prove tricky.

Jaba · Post by **Jaba** » Tue Jun 16, 2009 1:04 am

I presume that your aircon is no longer working.
First, has it been charged with R134a before ? You can check this by looking at the hose connection elbows on the compressor. If its still an R12 system then you will see a gas connector that looks like a tyre valve. If its been R134a converted there will be much larger quick fit connectors on the schrader valve(s).
The conversion that the aircon specialist talks about is simply to change the oil to PAG oil and fit the R134a quickfit connectors and fill up with a reduced quantity of refrigerant compared with the 1kg that R12 systems use.
It is essential to change the drier receiver at this time as well, as the old d/r does not work at all with R134a. The aircon still works but any moisture still circulates instead of being retained by the dessicant in the new d/r. The 'specialist' does not usually replace this.

There may be a leak in the system. Usually caused by the breakdown of one or more of the o-rings in the system.
It is usually best to replace ALL the o-rings in the system at conversion time. There are about 12 of them of 3 different sizes.
Personally I would remove the compressor, drain out the R12 mineral oil and refill with 150cc of ester oil which is compatible with R134a and mixes with the residues of the mineral oil still in the system, then replace all the o-rings, fit R134a connectors and a drier receiver then take it to a specialist for a leak test and regas stating DO NOT add any oil.

Way2go · Post by **Way2go** » Tue Jun 16, 2009 1:10 am

Jaba wrote:I presume that your aircon is no longer working.
First, has it been charged with R134a before ? You can check this by looking at the hose connection elbows on the compressor. If its still an R12 system then you will see a gas connector that looks like a tyre valve. If its been R134a converted there will be much larger quick fit connectors on the schrader valve(s).
The conversion that the aircon specialist talks about is simply to change the oil to PAG oil and fit the R134a quickfit connectors and fill up with a reduced quantity of refrigerant compared with the 1kg that R12 systems use.
It is essential to change the drier receiver at this time as well, as the old d/r does not work at all with R134a. The aircon still works but any moisture still circulates instead of being retained by the dessicant in the new d/r. The 'specialist' does not usually replace this.

There may be a leak in the system. Usually caused by the breakdown of one or more of the o-rings in the system.
It is usually best to replace ALL the o-rings in the system at conversion time. There are about 12 of them of 3 different sizes.
Personally I would remove the compressor, drain out the R12 mineral oil and refill with 150cc of ester oil which is compatible with R134a and mixes with the residues of the mineral oil still in the system, then replace all the o-rings, fit R134a connectors and a drier receiver then take it to a specialist for a leak test and regas stating DO NOT add any oil.

That is the most comprehensive yet concise post on converting a BX from R12 to R134a so far!

Well done Jaba.

Vanny · Post by **Vanny** » Tue Jun 16, 2009 1:53 am

I'm under the impression that it is possible to use an adapter neck to allow R134a quick fit recharge connectors to fit on R12 high and low side valves without having to have them permanantly converted? Is this possible? How easy is the valve conversion?

Jaba · Post by **Jaba** » Tue Jun 16, 2009 7:57 am

Vanny wrote:I'm under the impression that it is possible to use an adaptor neck to allow R134a quick fit recharge connectors to fit on R12 high and low side valves without having to have them permanently converted? Is this possible? How easy is the valve conversion?

Yes thats what they are. You remove the valve core from the existing and the new adaptor just screws on to the old schrader valve. They come with colour coded caps for the high and low sides.
The conversion can be reversed but why would you want to.
Staying cool, Jaba

Vanny · Post by **Vanny** » Tue Jun 16, 2009 11:33 pm

My impression was that you could have an adapter that connected one end to the r12 tyre valve and the other a quick fit connector, thus allowing an r12 connector system to be refilled with r134 without permanant conversion to a quick fit connector. I've check it out and such a device does exists (or you could even make your own for buttons), but as the replacement valve cores are so cheap i doubt there would be any point.

Checking out the valve core replacements, they are incredibly cheap (£1.50 to £5) and pretty easy to do. I expected it to be a cut and braise job TBH, very glad it isnt!

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More air con questions: Gas?

More air con questions: Gas?

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