64 52... Notes For Changing The Air Conditioning Compressor (Amount Of Refrigerant Oil Of New Air Conditioning Compressor Not Known)

Special tools required: 

• 00 9 030

A DIFFERENT PROCEDURE applies for air conditioning compressors with a label indicating the amount of refrigerant oil.

Air conditioning compressors with plastic belt pulleys: 

• Avoid impacts/knocks to plastic belt pulley (caused by tools, contact with base).
• Return faulty air conditioning compressors in their original packaging only.

• Switch on Air conditioning system.
• Set all air vents in the dashboard to "OPEN".
• Start engine and let it stabilize at idle speed.
• Set blower output to min. 75% of max. blower output.
• Switch on heating and air conditioning system and run for at least 2 minutes at idle speed  .

  Risk of damage at increased engine speed! 

All vehicles: 

• AIR CONDITIONING COMPRESSOR .
• Replace DESICCANT INSERT .
• Line to the capacitor.
• Refrigerant oil.

The new air conditioning compressor is filled at the factory with refrigerant oil.

The amount of refrigerant oil in the new air conditioning compressor corresponds to the amount of refrigerant oil for the entire new and unfilled  refrigerant circuit.

When replacing the air conditioning compressor it is absolutely essential to adapt the amount of refrigerant oil in accordance with the instructions below! 

The only time it is not necessary to adjust the amount of refrigerant oil is when replacing the entire  refrigerant circuit.

When evacuating the air conditioning system, refrigerant oil is also extracted and collected in the oil separator of the A/C service station.

After evacuation, the refrigerant must be filtered in the A/C service station as the oil separator could still contain a liquid refrigerant/oil mixture. The refrigerant completely gasifies through the cleaning operation. Only the prior bound refrigerant oil remains in the oil separator. Measure and note down this quantity of refrigerant oil.

Fig 1: Evacuating A/C System

Courtesy of BMW OF NORTH AMERICA, INC.

Refer To EVACUATING A/C SYSTEM .

Transfer the refrigerant oil remaining in the previous air conditioning compressor via the oil filler plug completely into a measuring cup.

Fig 2: Filling Refrigerant Oil

Courtesy of BMW OF NORTH AMERICA, INC.

Measure the amount of refrigerant oil collected from the previous air conditioning compressor.

Fig 3: Measuring Refrigerant Oil

Courtesy of BMW OF NORTH AMERICA, INC.

Open oil filler plug and pour entire contents of air conditioning compressor into a clean collecting vessel.

Installation note: 

Replace sealing rings.

Use special tool 00 9 030 to mount sealing rings without damaging them.

Observe tightening torque, 64 52 2AZ.  . See AIR CONDITIONING COMPRESSOR .

Fig 4: Draining Refrigerant Oil

Courtesy of BMW OF NORTH AMERICA, INC.

From the new air conditioning compressor, pour the same amount of refrigerant oil (as drained from the previous air conditioning compressor) + 10 ml extra  into a clean measuring cup and pour again into the new air conditioning compressor. At least but a total of 50 ml  .

Remaining refrigerant oil can be poured into A/C service station tank.

Refer To EVACUATING HEATING AND AIR CONDITIONING SYSTEM .

Otherwise the excess refrigerant oil must be disposed of correctly.

On account of its hygroscopic properties, refrigerant oil must not be stored in open containers.

Fig 5: Measuring Air Conditioning Compressor Fluid

Courtesy of BMW OF NORTH AMERICA, INC.

The refrigerant oil drawn off from the oil separator of the A/C service station and from the previous air conditioning compressor must not be reused and must be correctly disposed of.

Fig 6: Disposing Of Refrigerant Oil

Courtesy of BMW OF NORTH AMERICA, INC.

After installing the new air conditioning compressor, it is essential before filling the heating and air conditioning system to pour the same amount of the previously drawn off refrigerant oil into the system again.

Refer To EVACUATING HEATING AND AIR CONDITIONING SYSTEM .

Fig 7: Charging Air Conditioning Compressor

Courtesy of BMW OF NORTH AMERICA, INC.

Installation note: 

If the refrigerant circuit is open for longer than 24 hours: REPLACE DRYER FLASK/DESICCANT INSERT .