Rangie Air Con

[mczaf666]

Hi All,

Have recently purchased a 1984 RR.

Now is time to iron out a few bugs.

The air con needs regassing and need to know if R12 or an equivalent can still be purchased to regass rather than changing over to the newer aircon.

IVe read somwhere on the net that the older aircons can be recharged with LPG as it has very similar properties to r12 but im unsure if this is true, and if it is I dont know if I really want to try using it.

I would probably end up alot hotter than what I am know!!!

Regards

Hamish

[p38arover]

You can recharge it with R134. You'll need a new dryer. It wil still work OK. I had my '86 RR done.

[PhilipA]

Agree. I just had my 92 regassed with R134.
Apparently this was a nono up until now because the oils were incompatable, but now new oils make it an easy change over.
Mine works very well so far.
regards Philip A

[hiline]

Hi All,

Have recently purchased a 1984 RR.

Now is time to iron out a few bugs.

The air con needs regassing and need to know if R12 or an equivalent can still be purchased to regass rather than changing over to the newer aircon.

IVe read somwhere on the net that the older aircons can be recharged with LPG as it has very similar properties to r12 but im unsure if this is true, and if it is I dont know if I really want to try using it.

I would probably end up alot hotter than what I am know!!!

Regards

Hamish

Ladas is the man to ask

[TheLowRanger]

I had my 84 RRC regassed with the new stuff about 5 years ago without any problems. Only changed the receiver dryer which is no big deal.

[PLR]

G`day Hamish

Ours has an old piston compresssor like you most probably is .

Last year could still get R12 equivalent . ( i think the codes under the bonnet if you want it )

Ring around and get a quote . ( some commercial refrig places will do basic stuff cheaper than auto )

Ours still works at present

Cost was $80 or $90 can`t remember ( non auto ) , nothing was changed/replaced ( hardware ) and $20 or $30 of that was for fluro dye . ( leaks )

Also was told by 2 auto places , drier can stay if the system hasn`t been opened and the reason for gas loss is known .

Cheers

[ladas]

Hamish

Its a difficult area. To change to R134a - the system needs to be dismantled and flushed - to get all the old oil out - as mentioned below - oil is one of the main problems - however the oil used in R134a hasn't changed in many years - its still a POE type - the oil used with R12 was a minteral oil, and it is not fully compatible with R134a.

To do the job properly - if you want to go that route you need to replace the reciever drier - you would also need to consider either increasing the condenser coil size (R134a needs a bigger surface area to condense) - or get a bigger better condenser fan.

R134a will never work as well as R12 did due to the much lower critical temp - this is the point where the high pressure/high temperature vapour cannot be condensed into a high pressure medium temp fluid. The critical temp of R134a is 98 Deg C +/- whereas R12 the critical temp is approx 135 Deg C.

Now you may say it will never reach 98 Deg C @ the condenser - but unfortunately - this temp is achievable - and its also a relationship scale - meaning that even @ 60 Deg C the condensing effect is reduced - itsnot a direct % of 98Deg but a sliding scale.

So there you have the details on R134a - in my view it is the poorest refrigeration on the market for auto air applications (maybe okay for domestic refrigerators). Plus of course from an environmental issue - it has a very high GWP (Global Warming Potential).

Now you mentioned about LPG - well almost, not quite spot on - Hydrocarbons have been used in refrigeration and air conditioning systems since the very early 1900's - and its very good. Very efficient, zero ODP (ozone depletion potential) and minimal GWP (about 3 with an atmospheric life of less than 1 year - the GWP of R134a is 1500 with an atmospheric life of greater than 20 years).

Hydrocarbon refrigerants are highly refined common HC's like iso butane or propane - and very carefully blended to give the correct pressure temperature relationships.

Some people panic about putting HC's in auto AC systems - but when you look at the amount (typically 300 grams) compaired to the 60 - 90 ltrs (60 - 90 killograms) of petrol or diesel - or the 70 odd litres of LPG - and with that stuff its piped from one end of the vehicle to the other and 'burnt' - the 300 grams fades into insignificance.

In my opinion - for older R12 vehicle the best option is to save money and just have someone charge the system with HC refrigerants.

I would still recommend changing the reciever drier and all the o rings - as if the system has been 'empty or not used' for a while - these O rings dry out and perish.

Using HC's you can use the original oil - mineral - the same compressor, condenser, TX valve, evaporator - everything - and the critical temp is again back up to similar to that of R12.

You would need to find the original leak to find where the old gas went before charging - but the rest is easy.

If you want some more details / info on HC refrigerants - send me a PM

Hi All,

Have recently purchased a 1984 RR.

Now is time to iron out a few bugs.

The air con needs regassing and need to know if R12 or an equivalent can still be purchased to regass rather than changing over to the newer aircon.

IVe read somwhere on the net that the older aircons can be recharged with LPG as it has very similar properties to r12 but im unsure if this is true, and if it is I dont know if I really want to try using it.

I would probably end up alot hotter than what I am know!!!

Regards

Hamish

[mczaf666]

Thanks alot for all of your help and ideas


Hamish.

[Dougal]

I'm looking to recharge my aircon with LPG.

None of the car refrigeration guys in my area will touch anything but R134a, so I'm considering doing it myself.

First question, where can I get an adaptor to fit the original filling point? It's like a schraeder valve but the thread is bigger.

Second question, How do you determine the pressure or fill is sufficient? I've heard 30psi at the valve when the system is running.

[123rover50]

I'm looking to recharge my aircon with LPG.

None of the car refrigeration guys in my area will touch anything but R134a, so I'm considering doing it myself.

First question, where can I get an adaptor to fit the original filling point? It's like a schraeder valve but the thread is bigger.

Second question, How do you determine the pressure or fill is sufficient? I've heard 30psi at the valve when the system is running.

Any more info you can share about LPG?
I am running low on 143 and I probably wont be allowed to buy another.
Didiman