A/C Refrigerant: R12 (Freon) vs. R134a

Today, R12 (Freon) is no longer used because it damages ozone. Not only is R12 banned for sale in the US, but also to evacuate the refrigerant from your system, you have to be a licensed car repair shop. They want to make sure you have the proper equipment to contain the old refrigerant. Cars built in the USA after 1993 uses R134a as the A/C refrigerant. You can notice cars using R12 by noticing the valve on the low and high side of the refrigerant line. They uses valves similar to the ones you have on your wheels/tires.