Replacing Air Conditioning Compressor

NOTE: Fill level too low

Risk of damage to components.
→ Do not start the engine.

→ Do not tow the vehicle.

NOTE: Too much or too little refrigerant oil in air-conditioning circuit.

Reduced cooling output.
Lack of lubrication and failure of the air-conditioning compressor.
→ If a new air conditioning compressor or a component in the circuit is replaced, the oil quantity must be checked and adjusted.

Information

All connection points must be completely clean.

The air-conditioning compressor must be dry (washing the vehicle) and no moisture must get into the air-conditioning compressor and lines.

The connection points must be closed off after they have been opened. Use the original transport caps.

Information

If the air-conditioning compressor is blocked or seized up, then additional steps must be carried out to ensure that the air-conditioning system is working. See section on Work steps for blocked or seized up air-conditioning compressor

Information

New air-conditioning compressors are pressurised and filled with the total oil quantity required for the refrigerant circuit!
The remaining oil quantity in the individual components must therefore be taken into account!
Refrigerant oil from the compressor or refrigerant oil removed by suction from a previously run air-conditioning system may no longer be used (special-category waste)!
Determining oil quantity on the "old" air-conditioning compressor

First, open the caps on the high-pressure side and relieve the pressure from the compressor -A- .

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Cap and oil filler screw
Open the oil filler screw -B- on the air-conditioning compressor.
Fill the refrigerant oil from the air-conditioning compressor into the measuring cylinder. Turn the pressure plate before the pulley when emptying the refrigerant oil.
The amount of refrigerant oil is referred to as "V" in the formula below.
Always replace the sealing ring for the oil filler screw.
Screw oil filler screw -B- into the compressor.
Determining oil quantity on the "new" air-conditioning compressor

Courtesy of PORSCHE CARS NORTH AMERICA, INC.

Cap and oil filler screw

To drain refrigerant oil:
1. 1.1 First, open the cap on the high-pressure side and relieve the pressure from the compressor -A- .
2. 1.2 Open the oil filler screw -B- on the air-conditioning compressor.
3. 1.3 Drain refrigerant oil from the air-conditioning compressor.
  The refrigerant oil must not be re-used, but must be disposed of in accordance with regulations.
To determine the refrigerant oil quantity:
1. 2.1 V _total = "V _removed " + "V _old " + 20 cm³
2. 2.2 V _total = Total volume for the new air-conditioning compressor
3. 2.3 V _removed = Volume of refrigerant oil removed by suction
4. 2.4 V _old = Volume of refrigerant oil in the old air-conditioning compressor
5. 2.5 20 cm ³ = Additional safety volume
To fill the air-conditioning compressor:
1. 3.1 Fill the determined refrigerant oil volume V_total into the air-conditioning compressor.
2. 3.2 Always replace the sealing ring for the oil filler screw.
3. 3.3 Tighten oil filler screw -B- on the compressor to the prescribed tightening torque > Tightening torque 15 Nm (11 ftlb.)
4. 3.4 Install air-conditioning compressor
  > WM, 873419 REMOVING AND INSTALLING AIR CONDITIONING COMPRESSOR