Air Con Recharge

[Paul]

Does anyone know the dates when the coolants in the air con system changed ... and when they were and the coolants they changed from and to ... :?:

I need to check to see if my '96 JDM can be recharged in the same way with the same gas ... RS24 I recall ... that SteveCaz had his system recharged with.

However, if the change over is somewhere between ... or around ... '94 to '96 ... I need to be a little careful as whilst the lovely peeps DVLA have plated my NSX as a '96 ... the NSX mechanic at Reading Honda seems to think it may be as early as '94 ... partly due to it still having the fan in the engine bay on the opposite side from the air filter ... :!:

Any help would be grately appreciated ... I'm hoping to get my system recharged before JapFest ... thanks

[Steveycaz]

Does anyone know the dates when the coolants in the air con system changed ... and when they were and the coolants they changed from and to ... :?:

You can check visually Paul. The valves on the pipes where the refrigerant is drained/charged are very different in size between the R12 and later R134a systems. The R12 are smaller, with a valve cap about 1/2 inch across. The later ones are at least an inch across. I have seen both systems so could have a look at yours and compare it to mine (ooer!) if you like?

[Paul]

SteveCaz ... you have PM ...

[Paul]

Thanks for pointing out that I have small ones Steve ... mind you as yours are small you can't boast anyway ;-) ... thats small valves on our air con systems :-o

I'm now booked in to have my system recharged on Friday afternoon ... although with all this dull and wet weather ... maybe I could have left it anotehr week or two ... :lol:

[Paul]

All done! I now have a nicely cooled NSX again, although with the current weather it might be a few days before I need to actually use the air con!

Would be more than happy to recommend Neil [Cool Cars] for anyone who needs their system recharging, his number is in a previous post in this thread. He can recharge modern R134 systems, as well as recharging older R12 systems by using a modern day replacement coolant called RS24, the cost of the later being a paltry £70.

Many garages may tell you that your older R12 system will need converting, but what they probably won't tell you is that it is possible to use a modern and completely legal replacement coolant, R24, without the need to undertake a costly convertion. Although should you question why they can't just recharge it with RS24, they may well say they don't use that coolant, or can't, saying that they are only able to do a convertion for you.

Thanks to SteveCaz for his research into getting older systems recharged and for managing to find someone who can do it at a reasonable cost.

[TheSebringOne]

Size isn't everything Paul! You said R134 for newer air con systems, I assume my 99 is would use this?

[Paul]

Size isn't everything Paul! You said R134 for newer air con systems, I assume my 99 is would use this?

You'll need to check the two valves that are used to drain/recharge the system.
They can be located at the locations pointed to in the below image ... or at least they are in the locations indicated on my car ... maybe newer systems have the valve located in different places.
The valve near the headlight is the high pressure valve and should have a red coloured cap ... the valve lower down and further back near the bulkhead is the low pressure valve and should have a black cap on it.
If the caps on your valves are about half an inch across then you have an older R12 system which can be recharged with RS24.
If the caps are significantly more than about half an inch across then you have a newer system which I think is likely to use R134a :?: but you'll need to check first if your valves are of the larger variety.

[TheSebringOne]

Thanks Paul, did you draw that yourself? Lost vocation?! If so very impressive! Maybe a picture with digital camera might have been quicker?

[Paul]

Thanks Paul, did you draw that yourself? Lost vocation?! If so very impressive! Maybe a picture with digital camera might have been quicker?

I'd love to say it was a quick sketch I put together ... but alas it is just a section from a diagram in the service manual ... :p

[Steveycaz]

Well I got my R12 AirCon system recharged with RS24 in May as you can see from this thread. It did only cost £70 and it did work fine. Now though, 4 months down the line, I have almost no cold air coming through whatsoever. Anyone else had this problem?