Keeping Cool Without Ozone Depletion

Porsche air conditioning systems consist of five major components; the compressor, condenser, orifice expansion valve, evaporator and accumulator-dehydrator. These components perform the following functions.

1. The compressor brings in the refrigerant gas from the evaporator and compresses it for circulation through the system.

2. The condenser removes the heat from the refrigerant and condenses the gas to a liquid.

3. The orifice expansion valve, or tube, regulates the flow of high-pressure liquid refrigerant to the evaporator, thereby lowering the pressure.

4. The evaporator is used to cool, dry, and clean the air that enters the passenger coil

5. The accumulator dehydrator separates liquid refrigerant from the gas state before it enters the compressor and removes moisture from the system.

The introduction of HFC R-134a refrigerant has solved the environmental problems of CFC R-12, yet there are new issues, which have to be considered. Initial testing of HFC R-134a has shown that it requires higher operating pressures than that of CFC R-12 because it is less active than R-12. I his results in the gas changing to a liquid at a slower rate. As a result, we are confronted with differences, which have to be addressed when retrofitting the system.

Conclusion

What does all this mean to the Porsche owner? If you plan on keeping your Porsche for a few years, it may be necessary to upgrade your air conditioning system. If your system is currently not operating properly, you are a prime candidate to upgrade. The cost of R-12 refrigerant is now higher than R-134a and soon may be unavailable to recharge your system when it is repaired. When the existing supply of R-12 is exhausted, the demand for upgrading will increase as will the price. Although this is a repair that can be put off as long as your system is operating properly, it is important to understand what you will face if your air conditioning system goes down. Remember, it is important to stay cool.