Whether your vehicle has manual air conditioner (A/C) or an automatic temperature control system, it is generations ahead of the A/C systems found in vehicles a decade ago. Both automatic and manual A/C systems use electronic controls and interact extensively with other vehicle systems. Therefore, specific equipment is required to ensure proper diagnosis and service.
In addition, responding to environmental and legislative pressures, leading automakers have redesigned car, van and truck A/C systems to eliminate the use of R-12 (Freon), which has been shown to cause damage to the earth's ozone layer.
Most mid-1990s vehicles' A/C systems operate using an "ozone friendly" new refrigerant called R-134a. Ask your local auto service professional which type of refrigerant is used in the vehicle you own or are considering buying.
Don't worry, whether your car's A/C uses R-12 or R-134a, you'll still be able to stay cool on those hot summer days. That is, of course, as long as you keep it properly maintained. Since the EPA (Environmental Protection Agency) outlawed the sale of R-12 in small containers, the days of topping off a car's A/C with a quick shot of Freon are over.
Caution: Don't be fooled by so-called "drop in" replacements. The EPA has not approved anything other than original-type refrigerants for use in vehicle A/C systems. Some service industry experts also warn that unapproved refrigerant blends can cause significant and costly damage to A/C and other system components.