64 52 Notes for changing the air conditioning compressor (refrigerant oil level of new air conditioning compressor known)
A DIFFERENT PROCEDURE applies for air conditioning compressors without a label containing the refrigerant oil level.
Remove the air conditioning compressor without damaging and without the use of force!
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 and with sealed connected branches.
- Switch on air conditioning
- Set all nozzles 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 air conditioning and run for at least 2 minutes at idle speed
Risk of damage at increased engine speed!
In the event of a mechanical air conditioning compressor failure and the resulting ingress of chips into the refrigerant circuit, replace the following parts:
- air conditioning compressor
- Replace desiccant insert
- Line to the capacitor
- Refrigerant oil
Rinse the refrigerant circuit.
The new air conditioning compressor is filled at the factory with refrigerant oil.
The refrigerant oil level in the new air conditioning compressor corresponds to the refrigerant oil level for the entire new and unfilled refrigerant circuit.
When replacing the air conditioning compressor it is absolutely essential to adapt the refrigerant oil level in accordance with the instructions below!
An adaptation is also required for the replacement of the dryer flask.
An adaptation of the refrigerant oil level is not required in the following cases:
- Replacement of the complete refrigerant circuit.
When EVACUATING THE AIR CONDITIONING , refrigerant oil is also extracted and collected in the oil separator of the A/C service station.
This refrigerant oil level is displayed after the evacuation of the air conditioning on the display of the A/C service station.
Record the refrigerant oil level shown on the A/C service station display.
Determination of the refrigerant oil level to be filled in the new air conditioning compressor:
Transfer the refrigerant oil remaining in the previous air conditioning compressor via the oil filler plug completely into a measuring cup.
Read the refrigerant oil level on the measuring cup. Add 10 ml extra to the refrigerant oil level recorded as a precaution, but record at least a total of 50 ml.
Example:
20 ml read at measuring cup:
20 ml + 10 ml extra = 30 ml < 50 ml
refrigerant oil level to be filled in the new air conditioning compressor = 50 ml
Turn the belt pulley during the filling process.
This allows more refrigerant oil to flow out of the previous air conditioning compressor.
Open oil filler plug.
Tightening torque 64 52 2AZ .
Drain the following refrigerant oil level from the new air conditioning compressor into a clean measuring cup:
refrigerant oil level to be drained from the new air conditioning compressor = refrigerant oil level on the label for the new air conditioning compressor - refrigerant oil level to be filled in the new air conditioning compressor
Example:
refrigerant oil level stated on the label of the new air conditioning compressor: 150 ml
refrigerant oil level to be drained = 150 ml - 50 ml = 100 ml
100 ml must be drained from the new air conditioning compressor.
The drained new refrigerant oil can be filled into the expansion tank of the A/C service station after draining.
On account of its hygroscopic properties, refrigerant oil must not be stored in open collecting vessels.
If the new, drained refrigerant oil is not filled straight away into the expansion tank of the A/C service station, it must be disposed of properly.
After installing the new air conditioning compressor, it is essential that, before the system is filled with refrigerant, the air conditioning system is filled with the same amount of refrigerant oil as initially drawn off and noted.
- Refer to FILLING AIR CONDITIONING SYSTEM
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.
Observe country-specific waste disposal regulations.
Installation note:
If the refrigerant circuit is open for longer than 24 hours:
- Replace desiccant insert