Freon Recovery Procedure

PRECAUTIONS

Porsche models use refrigerant R-134a in the air conditioning system. Refrigerant R-134a and R-12 are not compatible with each other. Refrigerant oil, refrigerant hoses and other component used in a R-134a refrigerant system also differ from those used with a R-12 refrigerant system. Refer to the ``Air Conditioning Specifications'' chart to determine refrigerant usage.

REFRIGERANT RECOVERY PROCEDURE

The use of refrigerant recovery and recycling stations allows the recovery and reuse of refrigerant after contaminants and moisture have been removed. When servicing systems using R-134a refrigerant, use of specialized recycling equipment is required.
When using a recovery or recycling station, follow the manufacturer's operating instructions, noting the following:
1. Use extreme caution and observe all safety and service precautions related to use of refrigerants.
2. Connect refrigerant recycling station hoses to vehicle A/C service ports and recovery station inlet fitting. Hoses used should have shutoff devices or check valve within 12 inches of hose ends to minimize introduction of air into recycling station and to minimize amount of refrigerant release when hoses are disconnected.
3. Turn recycling station On to start recovery process. Allow recycling station to pump refrigerant from A/C system until station pressure gauge indicates vacuum.
4. After vehicle A/C system has been evacuated, close station inlet valve, if equipped.
5. Turn station Off. On some stations the pump will automatically be turned Off by a low pressure switch.
6. Allow vehicle A/C system to remain closed for approximately two minutes. Observe vacuum level indicated on gauge. If pressure does not rise, disconnect recycling station hoses.
7. If system pressure rises, repeat steps 3 through 6 until vacuum level remains stable for two minutes.
8. Service A/C system as necessary, then evacuate and recharge A/C system.

OIL LEVEL CHECK

Refrigerant oil used for a R-134a refrigerant system differs from that used with an R-12 refrigerant system. Refer to the ``Air Conditioning Specifications'' chart to determine refrigerant usage.

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1. Start engine and operate air conditioner for several minutes.
2. Stop engine, then discharge refrigerant from system.
3. Remove oil filler plug and rotate compressor rotor on clutch plate until TDC mark is visible.
4. Rotate clutch plate counterclockwise approximately 110°, then insert dipstick at an angle up to the stop.
5. Remove dipstick and read oil level. Oil level should be between the seventh and eleventh graduations on dipstick. Add oil as necessary. A dipstick can be fabricated from a piece of suitable rod. Oil level should be 13/16 to 1 3/16 inch from end of rod.
6. Install oil fill plug, then charge refrigerant system.

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No provision is made for checking oil on these vehicles. Oil is added according to component(s) being replaced. Refer to ``Oil Charge.''

OIL CHARGE
Refrigerant oil used for a R-134a refrigerant system differs from that used with an R-12 refrigerant system. Refer to the ``Air Conditioning Specifications'' chart to determine refrigerant usage.

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New compressors are pre-charged with the proper amount of lubricant needed for the entire refrigerant system. If a new compressor is installed and no additional oil has been lost from the system, drain all oil from new compressor, then add 8 ounces of oil to compressor.
When replacing system components, add the following quantities of refrigerant oil to the compressor: condenser, 1 ounce; evaporator, 2 ounces; receiver-dryer, .3 ounce.

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Refer to ``Oil Level Check'' procedure.