Air Conditioning Refrigerant Alert

The purpose of this bulletin is to provide information about the use of a new type of air conditioning refrigerant that requires attention during the collision repair process. The reason for concern is primarily due to the chemical differences between the current and new refrigerants. The existing fluid, commonly referred to as R12, is chlorofluorocarbon (CFC) based, whereas the new refrigerant, R134a, is hydrofluorocarbon (HFC) based.

The body repair and insurance industries need to be aware that some new 1993 model vehicles contain the R134a refrigerant in their air conditioning systems. If the vehicle air conditioning refrigerant originally specified is R134a, R12 cannot be substituted without causing permanent damage and possible air conditioning system failure. Conversely, any system originally designed to use R12 cannot use R134a without sustaining permanent damage and possible system failure. However, consideration is being given to designing a retrofit kit for certain model vehicles, which after installation would allow the use of R134a in former R12 systems.

Why is the refrigerant being changed?

There are several environmental reasons why chlorofluorocarbon refrigerants are being phased out of use in mobile air conditioning systems. The most important is the effect of R12 on the ozone layer in the atmosphere. As chlorofluorocarbon fluids escape into the atmosphere due to leaks or collision damage, ozone molecules in the air are absorbed by the chlorofluorocarbon molecules. This action results in a depletion of the ozone layer, which in turn allows higher levels of ultra violet rays from the sun to penetrate the lower atmosphere. This in turn could result in an increase in the occurrence or severity of human skin cancer as well as other health related issues.

Many nations were concerned enough about ozone depletion to sign the "Montreal Protocol" in 1991, which calls for international efforts to reduce and/or eliminate CFC's released into the atmosphere. This has to be a long term commitment since CFC's remain in the atmosphere for up to 100 years. HFC based refrigerants also absorb ozone, but at a significantly lower rate than CFC's. Research is continuing to find new refrigerants that will not absorb any ozone.

The U.S. Environmental Protection Agency has announced regulations that require service operations to minimize or prevent the release of R12 type refrigerants into the air. As a result, R12 production will be stopped after 1995 in the U.S. Other countries in Europe will ban R12 production at the end of 1994.

What are the major problems that result when R12 and R134a systems are mixed together?

The major differences between CFC and HFC refrigerants are their relative abilities to transfer heat to metallic components efficiently. Tests have shown that the use of R134a in a system originally designed for R12 results in significantly higher compressor discharge pressures for a minimum increase in performance. This frequently results in higher stresses on the compressor and subsequent failure. Other problems result from compressor lubricant incompatibility, degradation of rubber seals and o-rings, and corrosion/copper plating of steel components. Finally, contamination from air introduced through rubber porosity and incompatible lubricants may cause false sight glass readings resulting in premature compressor failure.

What can be done to minimize contamination of refrigerants due to accidental or inadvertent mixing of R134a and R12?

The automotive service and repair industries need to observe the following guidelines for discharge of refrigerant, and recovery and recharging of air conditioning systems that utilize R134a refrigerants:

• Identify vehicles that use R134a by looking for the label on the underside of the hood or on the radiator core support.
• Recovery systems for handling R134a should not be used for R12. A separate system must be used for each type of refrigerant.
• Both R12 and R134a refrigerants must be recovered and recycled.
• Use correct discharging, recovery and recycling procedures according to equipment manufacturer instructions.

Compressor lubricant should be recovered and disposed of in a manner that conforms to all federal, state and local requirements.

How can vehicles with R134a refrigerant be identified?

Below is a list of 1993 model vehicles known to use R134a refrigerant. However, a decal under the hood or the repair manual will verify the use of R134a in each vehicle. This list may be incomplete as new models are also likely to use R134a as an air conditioning refrigerant.

1993 Model Year Vehicles Using R134a
BMW	318i/S 325i/S 525i 525iT 535i
Chrysler	Chrysler Concorde Dodge Intrepid Eagle Vision Dodge Viper Jeep Grand Cherokee Chrysler Town & Country Dodge Caravan Plymouth Voyager
Honda	NSX Legend Prelude
Nissan	Altima Pathfinder Truck
Infiniti	J30
Porsche	All Models / Jan 1993
Saab	9000
Toyota	Lexus LS400
Volvo	All U.S. Specification Models
VW/Audi	Golf Jetta EuroVan Audi 90 Audi 90 Quattro

The information provided in this bulletin is for educational purposes only. Although every effort has been made to ensure the accuracy of the information contained in this bulletin, Tech-Cor assumes no responsibility or liability for any repairs performed using information from any publication issued by Tech-Cor.

Any person performing repairs must determine whether any suggested or recommended procedures or repairs are suitable or appropriate for the particular vehicle being repaired. The repairer remains solely responsible for such determination, as well as for the proper completion of the repairs.

Reproduction of this bulletin is not permitted without the written approval of Tech-Cor.