Just to let the ace owners in Bournemouth know that I have been looking for a local specialist to convert my twin air conditioning system from R12 to R134 gas. I had been quoted £200 to £300 by three specialists for the conversion, then found Samson Motor Engineers on the Ferndown Industrial Estate (phone 01 202 893 660 )

They couldn’t convert to R134 as they couldn't get the conversion kits, which apparently cost loads of money. Instead they performed a full service and recharged the system with RS24 Liquid gas for a total cost of £77.55 inc VAT.

- (#8378) dave Bright, 7 May 03 6:27

Oh no!
This is industrial refrigerant, used in the lorry refrigeration units on the tops of trucks delivering to your local supermarkets, not really suitable for vehicle air con, as it's designed to be used in much bigger systems. Also I'm not sure if it's compatable with the mineral oil that would have been in the R12 system. Additionally did they change the receiver drier, if not then this could also cause problems, as they only retain a teaspoonful of moisture & if not changed could spill their contents of silica gel all through the a/c system. I'm afraid that whilst the job may have been cheap, it is really a case of you get what you pay for!

- (#8379) Rob Drinkwater, 7 May 03 16:28

Hi Rob
I was a bit worried by this, so I have had a ring round some other specialists to try to allay my fears, and this is what I have found.
Your right about the industrial refrigerant used in lorries etc. All the specialists say it is not suitable for vehicle air conditioning systems, but that is R22 gas, not RS24 gas.

RS24 gas is fairly new, and was developed to overcome the high cost of converting to R134a. It is a direct equivalent drop in gas to R12, with out the CFC’s, and is entirely compatible with the mineral oil and air con system. I have phoned Samson and they assure me that they have been installing RS24 for over two years with no reported problems so far.

- (#8380) dave Bright, 8 May 03 2:55

RS24 is a 'blended' drop in gas, that is designed for use in industrial units to overcome the problems there with CFC gases, it was only as an afterthought they put it into cars, it has a different moleculat weight to R12 or R134a, there is still no substitute for flushing out the system & putting in R134a with the conversion kit & oil, the 'blend' gases are only a bodge it & leg it measure!!!

- (#8381) Rob Drinkwater, 8 May 03 13:19

And yet Rob many Air con specialists, all over the world, both big and small are using it.

In Aus I have been recommended to use it by no less than three.
A US web site also promotes it.
So that is three countries (at least), all relatively advanced in these things, and all have companies willing to promote this as a viable alternative.

It may very well have been developed for industrial units, but reputable companies recommend it for cars.

Although it is less efficient than the original R12, so is R134.

And even though you will eventually need to convert, you probably would have to re-gass by then with or without a conversion, so why not save some money now?

Dave

- (#8382) DaveW, 8 May 03 19:52

Can't really see what the fuss is about with 'blend' gasses, I have pure R134a in mine, I did the conversion myself, no gas was in the system anyway, so no R12 to remove, put converters on the charge ports, changed receiver drier as a matter of course (must be changed with any change of gas, every 3 years or if the system has been cracked open for ANY reason) vacuumed the system down for 1 & a half hours, then put 200ml of PAO 68 universal oil, regassed with 15% less than the original weight of R12 with pure virgin R134a. So long as the seals that come off the receiver drier are green or orange (neoprene) & not black (Natural Rubber) then R134a should not damage them, to my knowledge (and certainly on our 1991 Townace) the Townies have neoprene seals, so no need for the 'blend' gases, if you can get the compressor off & flush the system through then even better, this will remove much of the mineral oil, but if not the PAO68 oil will float across it & not mix with it. Another problem with blend gases is that they 'separate out' in the cylinder, so the blend put into each vehicle can vary, so therefore efficiency can also vary. Did our conversion early last year & a/c is perfect, does what it's supposed to do.

- (#8441) Rob Drinkwater, 9 May 03 12:06