AC coolant phaseout

["EREC - DUNCAN, CAMERON" <CDUNCAN@smtpgate.nciinc.com>]

I understand the federal government has scheduled the production phaseout of 
freon, R-12, by the end of 1995. I asked a mechanic if the replacement 
coolant, HFC-134a, caused a problem in the AC system (it does in many 
systems). All I got out of him was that coolant conversion would be costly. 
Does anyone know ...
     1) anyone who has converted their AC to HFC-134a?
     2) if HFC-134a attacks the AC system enough to require,
          a) only an upgrade kit (cost? vendor?)
          b) system component replacement (cost? vendor?)
          c) other?
     3) the life of Audi AC systems

I understand there is an alternative refrigerant (blend),GHG (or R-406a), 
claiming to be the savior of R-12 refrigeration systems. The following 
manufacturer's information will sound like what it is--marketing. I really 
don't know any more about this issue, but many of us will be faced with what 
to do about our auto AC next summer.

          Monroe Air Tech
          522 West 2nd Street
          Bloomington, IN 47403
          Toll-free: (800) 424-3836
          Local:    (812) 331-7215
          Fax:      (812) 332-2284
"a direct drop-in refrigerant for R-12...Compatible with R-12 
systems...works well with existing hoses, valves, gaskets, oils, and seals 
found in R-12 systems including mineral oil and alkyl-benzene oil (including 
many dessicants in R-12 systems)...installs with the same equipment used to 
install R-12...priced competitive with R-12." Systems charged with GHC are 
tagged with a plastic laminated tag describing the blend and emergency phone 
numbers (tags included with cannisters)."

I don't know yet whether this has been used in automobile AC systems. If the 
phaseout of R-12 causes the cost of R-12 to rise dramatically, system 
conversion ($250-$1000 average), or high-priced alternatives, a lot of folk 
will be upset. I don't plan on being surprised. Some now recommend auto AC 
owners service the systems this winter before the phaseout. What do you 
think? Comments/thoughts??

Cameron Duncan
(Energy Efficiency and Renewable Energy Clearinghouse [EREC]--work 
disclaimer)
(1991 Audi 200S sedan)
E-mail: cameron.duncan@nciinc.com