Non-Approved Air Conditioning Refrigerants

NON-APPROVED AIR CONDITIONING REFRIGERANTS

Recently, "alternative" refrigerants for automatic air conditioning have been marketed in certain areas. These refrigerants are claimed to be compatible replacements for the BMW- approved R-12 refrigerant (also known as Freon[R]) The "alternative" refrigerants usually consist of a mixture of various components; among then may be R-12, R-22, R-142b, R-176, isobutane, propane or ammonia.

These refrigerant components are not related to, and not as ecologically sound as, the new R-134a refrigerant.

THIS TYPE OF "ALTERNATIVE" REFRIGERANTS IS NOT COMPATIBLE WITH, AND NOT APPROVED FOR USE IN BMW AIR CONDITIONING SYSTEMS.

Problems than can occur when charging a BMW air conditioning system with an alternative mix or "blend":

1. R-22 is incompatible with the existing R-12 desiccant found in BMW receiver-dryers. The desiccant will break down, and may be distributed through the A/C system, clogging the expansion valve and destroying the compressor. Some products use "sealants" which can clog orifices in both the vehicle and recycling equipment.
2. R-22 can result in substantially higher pressure when installed in a system designed for R-12, especially in stop-and-go traffic in high ambient temperatures.
3. Current R-12 hoses, O-rings and sealing materials found on BMW vehicles are not designed to, and do not, retain R-22. The R-22 permeates out of the hoses. If the R-12 is then lost from the system, the remaining R-142b is flammable.
4. If a vehicle with a non-approved refrigerant is brought into a shop and connected to recycling equipment, the same problems can occur with the recycling equipment. In addition, the "alternative" refrigerant can be passed on to other vehicles that are connected to the same recycling equipment. This could spread the problems to other vehicles.
5. Materials such as propane and isobutane are flammable. If the proper pressure and charge conditions are not maintained, these components "fractionate" out of the mixture. While the blended components may not be flammable, the individual components may be flammable if the mixture has fractionated.
6. Automotive A/C systems are subject to Federal law, as well as specific state requirements. Currently, 10 states and the District of Columbia have enacted requirements that generally follow SAE definitions and requirements. The SAE J639 standard requires that "...Blend refrigerants, both in the original composition and in the compositions created as a result of normal mobile air-conditioning operating conditions, must meet the previous [ASHRAE 34-78] criteria: low toxicity, nonflammable, and nonexplosive requirements."
7. Blend refrigerants often require costly special processing to recycle. Since they cannot be vented to the atmosphere, servicing the system requires removal of the material into dedicated containers and shipping the material to a processing center for reclamation or destruction. The shipping must be done according to state and federal regulations, and the material is classified as a flammable gas for shipping purposes.

Solution:

There are currently no BMW-approved alternative refrigerants to R-12 or R-134a.
Use of any refrigerant other than R-12 or R-134a will preclude warranty coverage of resulting failures.

Protect your customer's air conditioning systems as well as your own recycling equipment. Do not allow non-approved refrigerants to enter your recycling equipment.

If a customer has had air conditioning service performed elsewhere, determine that only approved refrigerant was used for recharging the system. This Service Information can be used to explain potential problems to customers.

SYSTEM CONVERSION

WHEN TO RETROFIT

As long as R-12 is available, it should be used to service a vehicle with an R-12 system.

When R-12 supplies are unavailable, the customers may be willing to pay for a retrofit.

STANDARD RETROFIT

To achieve the most effective system retrofit, follow the instructions in Service Information Bulletin # 64 O1 95 (4179). Retrofit kits have been developed for the E31, E32, E34, and E36 models, to provide comparable system performance. The kits include a new receiver/dryer; hoses, service fitting, refrigerant controls, and other parts.