A/C Systems - New HFC-134A Description: Overview

9230bmw01

Group 64
Heating and Air Conditioning


Bulletin Number
64 01 92 (2121)


Woodcliff Lake, NJ
April 1992
Product Engineering


SUBJECT:
New BMW HFC -134a Air Conditioning Systems

This Technical Reference Information bulletin will introduce the new refrigerant, HFC-134a, as well as describe important handling, servicing, and safety procedures pertinent to the new BMW air conditioning systems.

MODEL:
All (for model introduction dates please refer to section below)

Situation:
Due to new concerns about our environment and the effects of air conditioning refrigerants released into the atmosphere, BMW has developed automotive air conditioning systems for BMW vehicles that use the new environmentally friendly refrigerant HFC-134a (also known as R134a).

Note:
Freon(R) is a brand of R-12 manufactured by Dupont, Suva(R) Trans A/C is a brand of HFC-134a manufactured by Dupont. KLEA(R) is a brand of HFC-134a manufactured by ICI Chemicals and Polymers. This TRI will from here on refer to these refrigerants by their generic "service" names, R-12 and R-134a.

Introduction
Schedule:
March 1992 Production: E32/M30

August 1992 Production: E34/All Engines, E36/All Engines, E30
Convertible/All Engines, E31/M70, E32/M70

Enviromental
Information:
One of the most important issues in environmental protection is the problem of ozone depletion potential (ODP). The stratospheric ozone layer is responsible for protecting life on earth from the harmful UV spectrum of rays from the sun.

However, it has been found that some refrigerants used in air-conditioning systems contribute to the destruction of the stratospheric ozone layer. In addition, the level of gases such as CFCs (refrigerants/propellants), oxides of carbon and nitrogen, methane, etc. is increasing. These so-called "greenhouse gasses" cause heat radiated from the surface of the earth to be reflected from the atmosphere back down to the earth. Over a period of several years this increases the average temperature of the earth, much in the same way a vehicle interior becomes so hot on a sunny day. This effect is often referred to as the "greenhouse effect" or "global warming potential" (GWP). The atmospheric release of R-12 is adding to the "greenhouse effect" as well as contributing to ozone depletion.





Since a large percentage of the refrigerant vented into the atmosphere comes from automobiles, BMW has designed a new air conditioning system that employs R-134a as a refrigerant. R-134a is a much more environmentally sound refrigerant that R-12. Although R-134a still has global warming properties (and therefore, MUST be recycled - never vented into the atmosphere), R-134a has no ozone depleting potential. Refer to chart.