A/C System - R12 to R134a Conversion/Retrofit: Overview
SI No. 854-1801PI No. 5/94 Group 8
Date July 1997
Distr. US
900/9000
R12 to R134a Conversion/Retrofit of A/C System
Cars Affected:
-1993 900, -1994 900 Convertibles and -1992 9000 Models with R12 Refrigerant
Items on hand:
R134a Charging Equipment
R134a Refrigerant
IMPORTANT
When carrying out conversion of the NC system, the usual practice with regard to the high-pressure and low-pressure sides when draining and filling refrigerant is disregarded. Carefully follow the color directions in the method description and on the diagram.
Background
Earlier bulletin PSI 08/95-0610 covered the procedure to convert or retrofit a R12 to R134a A/C system. This bulletin repeats the information contained in that bulletin but adds information for retrofitting or converting 9000 models equipped with rear AC. See information specific to this model.
A method to convert R12 refrigerant-equipped systems to R134a refrigerant-equipped systems is now available. Briefly, this conversion consists first of purging the system of R12 completely and then rinsing it with R12 repeatedly until all the old compressor oil has been removed. This is followed by fitting a new receiver and filling with fresh compressor oil. Then, the system is filled with R134a refrigerant.
Because the mineral oil contained in R12 systems is Incompatible with that used in R134a systems, the compressor oil must also be changed when carrying out a conversion. Ester oils only should be used in A/C systems converted to R134a refrigerant. Note that this applies only to converted systems. PAG oil only is to be used in A/C systems filled from the factory with R134a. All old mineral oil must be removed or it will be deposited as an insulating film in the evaporator and have a noticeably adverse effect on A/C performance.
A kit has been developed that takes into account all versions all versions possible for performing this retrofit program. See specific applications.
WARNING
Frostbite could result if you get refrigerant on your bare skin or in your eyes. Wear protective gloves and goggles and use extraction equipment when working with refrigerant. Position the extraction equipment at the service connections of the A/C system and the discharge outlet of the purging equipment's vacuum pump.
Under no circumstances should the engine be started while working on the A/C system.
IMPORTANT
When carrying out conversion of the A/C system, the usual practice with regard to the high-pressure and low-pressure sides when draining and filling refrigerant is disregarded. Carefully follow the color directions in the method description and on the diagram.
Materials
A/C Conversion Kit (consisting of flushing kit, necessary adapters): J41601* $154.25
R12 Tank: J38100-30 $79.50
Above items available for ordering directly from Kent-Moore at 1-800-345-2233.
*Conversion kit will fit a variety of recycling units such as Bear Models 40-310, 40AI0, 40-327, 40- 370, 40-470; Mac Tool AC 17700, OTC Models OEM 1380,1396, 1397 and 1420; Robinair Models 17700,17400, 17350C, 17300,17301 and 17303.
Items shown should be ordered from Saab, dependent upon model being converted.
Spare parts set (consisting of receiver drier, pressure switch - 9000 only, labels, service nipples for R134a, compressor (ester) oil):
900 1982-1986 (incl. Convertible): 74 96 342
900 1987-1989 (incl. Convertible): 74 96 359
900 1990-1993, Convertible 1990-1994: 74 96 367
9000 1986-1989: 74 96 375
9000 1990-1991: 74 96 466
9000 1992- (including rear A/C equipped):
74 96 383