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Discussion Starter #1
Has anyone converted their air-con from the old gas to the new?
I know you need to repace the drier and flush the system of oil but is there anything else to do? Has anyone had problems?
Thanks in advance.
Dan.
 

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Dan
There should be no issues assuming there were none with operation on
R12 previously.

You will need a LP charge port & and an HP charge port.

You must flush the system & remove as much of the R12 & its gas / oil mix.
The oil mix in R12 reacts very badly with oil in R134a.
It becomes a gelled mess.

The reciever drier is an often neglected part.
It should be changed every 10 yrs / 100k miles.
It must be changed as part of the conversion to R134a.

system pressure is about 40-45 psi on the low pressure side.

Issues resulting from neglect & wear & tear are cracked condensors,
collapsed receiver driers blocking the system.
Hardened O rings where system has not been regularly cycled.
Cooked trinary switches etc.
The compressors are generally very reliable & problems are generally limited
to Electro-mechanical clutch plates burning out.

Cheers
 

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I haven't got time to start searching at the moment, but isn't the one of the items (either the compressor or condenser) different on the old gas to the new one, and was a 3.8 part only.

I definately remember more than one person having issues with the mounting of the new parts and having to fabricate or modify a bracket.

I will look when I have a second.

Regards

Ivan
 

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Hi
As long as the system is vacuum purged & there are not issues already
existing, it should be fine using existing 3.6 compressor.
Not sure about condensor, but I am not aware of any functional issues on the parts.
Hope not.
We have serviced & converted one early 3.6 & its running around on R134a
just fine...at the moment;), but we changed all the gaskets & "O" rings.
The issue lies mainly with old "O" rings & gaskets that were potentially susceptable to
being broken down by R134A.
New "O" rings & gaskets should be fitted on an old system about to be converted as part of the service.

R12 is a much more efficient refridgerant medium than R134a but its also much
more of an atmospheric pollutant, hence its demise.


Cheers
Farrell
 

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My Aircon was moved to the new gas by my neighbour who is an aircon specialist.
I had a knackered condenser/fan with a whole behind the fan, so I replaced the condenser and drier as it had been open to atmosphere for a while. We removed the oil and any remnants of gas, replaced the drier and consdenser and replaced the O'rings which were particularly perished already in fairness.

He replaced the two valves and did a vacuum on it for approximately 45 minutes to ensure as much moisture/air was removed as possible then refilled with the new oil and gas along with a uv dye to show any potential leaks. I replaced the fan with one form a 7 series which was identical. the R134a isnt as efficient as the old gas but does work. He did mention to me the other day there is a new replacement gas which has some booster to increase cooling potential to nearly that of R12, so when he gives me more details I may give it a try especially with summer coming and all :)
 

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Discussion Starter #6
Thanks everyone, IF I could get hold of some R12 would it make sense to just recharge the system with it?
I'm only considering the conversion as I'll have to do it when R12 is all gone/banned - if its not already.
My air-con works but just isn't very cold.
How long does a charge last assuming no leaks?
 

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Dan
The system capacity is 1650gms of oil & gas @ operating pressure.
The system makes up for in sheer size, what it lacks in outright efficiency.
There are parasitic losses in all a/c systems.
This becomes worse with lack of use as "O" rings dry up when oil / gas mixture
is not circulated.

It could go 24 months between charges.
It could go 12 months.

R12 is more expensive as a refridegerant medium.
Most do not deal with it these days.
Due to the CFC atmospheric pollution issues, there are steps being taken
to prevent the publics access even to R134a, let alone R12.
All to do with recovery & recharge best practices.

I woud suggest that if you view the car as a long term tenure, then conversion
is the way forward.

Cheers
Farrell
 
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