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Maintaining and Recharging Your A/C

Car care to keep you cool

Despite what you may have read on the Internet, or heard from certain late night AM radio hosts, there is no secret government agenda to make us all run banana oil or mind control serum cleverly disguised as refrigerant in our automotive air conditioner systems.

Refrigerant Types

Automotive AC systems rely on one of two refrigerants to keep things cool in the cabin. Vehicles made before 1993 use R12, or Freon®, and vehicles made after use 134a. R12 refrigerant is no longer available to the consumer because of environmental concerns, but is still available for use by trained technicians and installers. In fact, the main reason R12 is still available is these same technicians have continued to recycle, clean, and reuse the remaining supply. New R12 is no longer being manufactured.

This was the whole point of the laws in the first place. Amateurs were venting R12 into the atmosphere, which was rumored to put holes in the ozone layer, causing a case of permanent sunburn for the entire planet. The decision was made to regulate the use of R12 for safety's sake. If your vehicle was made before 1993, there's a great probability that it uses R12, or Freon®, as a refrigerant. After 1993, all vehicles in the United States were required by the EPA to use 134a as a refrigerant. The future holds even more refrigerant alternatives but, for the time being, these two refrigerants are the heavy hitters of automotive air conditioning systems.

Tested As Charged

The first reaction when an AC system stops working is to bust out the refrigerant and go recharging crazy. Recharging a leaky system is not only a waste of money and time, but is a temporary fix at best—and may contribute to the aforementioned planetary permanent sunburn problem, even with the new and improved refrigerant. Conversely, overcharging an AC system can actually decrease performance and work against the production of cooling interior breezes. Also note that attempting to charge an R12 system with a can of 134a can not only lead to problems, but can also be dangerous, as the two refrigerants are not compatible.

While the refrigerant itself is a major player in the hot-air-into-cool-breeze act of the air conditioning system, it is only one player on the team. The compressor, condenser, evaporator, and all hoses, o-rings, vents and gizmos must be working together to bring the cool winds flowing across your face inside the vehicle on a hot summer day. If the air conditioning system is losing refrigerant, the compressor isn't compressing, or the evaporator has evaporated. There is no great conspiracy afoot, just leaks not keeping the refrigerant inside where it belongs, or component parts that have gone kaput.

Switch Or Fight?

Determining what's wrong with the AC system is the first step to take in bringing back the chill. Malfunctions can be caused by something as simple as a plastic grocery bag stuck in a vent, a recalcitrant relay, or a broken compressor drive belt. While a small amount of refrigerant leakage occurs over time, major leaks should be found and repaired first before attempting to recharge an AC system. To determine what's going on with an AC system, the best bet is to take the vehicle to an authorized repair center. A technician can test the system for leaks, measure temperature output, determine which components are working or not, and recharge the system in one motion, if all is well.

Switching over to an R134a refrigerant may be the solution to a leaking R12 system if the components are worn enough to justify replacement with updated parts. The high and low pressure hoses, o-rings, and all associated junctions must be updated to work with R134a if the decision is made to switch, rather than fight. The many cars that still run with R12 can be serviced, but if removal and replacement of a compressor or condenser is required, a switch to 134a may be a good call. Updating the hoses, o-rings and components to work with 134a is best done when the system is apart and discharged. Special thanks go out to diagnostics and emissions specialist Arthur Kuyudjyan at Glendale Service Center for help in creating this article.