I think the problem is more the oil, and not the pressures. Sure the average pressure with R134a will be a bit higher (maybe 10%), but because the R12 pressure switches are still in place the maximum pressure will be the same. Converting to R134a without replacing the oil is a problem. The mineral oil used with R12 is not miscible with R134a; this means that the oil won't flow in the system to lubricate the compressor. The best way to retrofit is to flush the system and replace the mineral oil with double-end-capped PAG or POE. PAG is shown to lubricate better than POE, but it's not as compatible with different refrigerants; specifically double-end-capped PAG is the best at resisting moisture absorption. Without flushing the system it's possible to just add the replacement oil on top of the mineral oil. No ideal as it will reduce cooling among other things but better than nothing. Ryan On Thu, May 9, 2013 at 7:53 AM, JRodgers <jrodgers113@gmail.com> wrote: > Tom, > > Thanks for putting this out there. Probably the single biggest factor > with a Vanagon in converting to 134a is the compressor. I find my van AC > is adequate with the 134a. I have not had the problem- yet - but from > what I understand, the compressors often fail when the 134a is used > because they are not designed for the higher pressures that are required > by the 134a. > > NEW later model Sanden compressors that fit the Vanagon and are designed > for 134a can be had from the 'Bay" for around $200 or so. A while back I > looked at one for $215. > > John |
Please note - During the past 17 years of operation, several gigabytes of
Vanagon mail messages have been archived. Searching the entire collection
will take up to five minutes to complete. Please be patient!
Return to the archives @ gerry.vanagon.com
The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.
Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.