Does anyone know how many cans of freeon it takes to charge the air conditioner

It depends on what size cans of freon you are getting and if the system has been retrofitted for R-134A refrigerant (1992 came originally equipped with an R-12 system). The factory specifications call for 1.8 Lbs. of R-12. If it has been retrofitted for R-134A, the general "rule-of-thumb" is 85% of the R-12 specification is needed to charge the system with R-134A. So if we do the math: 1.8 Lbs (R-12) X .85 (R-134A) = 1.53 Lbs. R-134A needed for a full recharge (providing the system is COMPLETELY empty. Then you will have to find out how much is in each can that you plan to buy and do the math to figure out how many cans you need. (some have 12 oz., some have 14 oz., some have 16 oz., some have 19 oz. and some have 22 oz.)