BMW X5: Refrigeration Oil
OIL USED IN FREON-CHARGED SYSTEMS
A mineral-based oil is used. The oil level in the compressor must be checked before filling an air conditioner with refrigerant. It can be checked only if the system is without refrigerant.
Always check the oil level each time a new system is filled with Freon R12 or after repairs. The oil level is very important for the entire air conditioning system. Part of the oil (approx. 25% depending on amount of refrigerant) is mixed with the refrigerant and is continuously circulated in the system. This oil lubricates the moving parts of the system, such as the expansion valve and compressor.
Oil Used in R-134a-Charged Systems:
A synthetic oil is used, which is totally different than the mineral-based oils used in Freon R12 systems.
R-134a systems require Polyalkylene Glycol lubricants, often referred to as "PAG" oil. Use of R-12 compressor oil in R-134a systems will cause the compressor to seize and fail. The R-12 mineral oil does not stay in solution in R-134a. In addition, R-134a compressor should not be used in an R-12 system. Long term damage and corrosion will result.
The GREEN R-134a system labels, usually located near the top side of the fan shroud in the engine compartment, will display the refrigerant requirement for R-134a systems. An example is illustrated.
R-12 systems will have a BLACK label in a similar location.
Fig. 1: Identifying R-12 Systems - Black Label
PAG oil should only be stored in its original container, and sealed as tightly as possible. PAG oil is totally devoid of moisture when packaged, and will absorb moisture readily (hygroscopic) if exposed to the atmosphere, rendering it useless. Dispose of all extracted lubricants from A/C systems. Never reuse old compressor oil. Contaminated PAG oil should never be added to the air-conditioning system, and old PAG oil is typically contaminated with moisture. R-134a is even more sensitive to moisture contamination than R-12 systems.
PAG oil may be obtained from BMW of North America.
BMW Part No. 82 11 1 468 042.
READ NEXT:
Air Conditioning Unit Disinfectants
A musty odor may be detected in the vehicle, particularly when the air
conditioner is first switched on.
This is caused by microorganisms growing on the evaporator from moisture
condensation.
A di
Overview Of Heater/Air Conditioner Servomotors
Fig. 1: Identifying Heater/Air Conditioner Servomotors Components Location
Servomotor, defrosting
Servomotor, footwell, rear cabin right
Servomotor, ventilation, front right
Servomotor, stratifi
SEE MORE:
Air Conditioner Test (R 134A)
Before A/C efficiency test, satisfy following conditions:
1. Provide a MoDiC or DIS. Safeguard electrical system integrity by checking
the fault memory (no faults
in the fault memory).
2. Provide a thermometer with separate gauge.
3. Perform the test in a suitable work bay with an ambient temperat
Replacing Exhaust Camshaft Pulse Generator (N52, N52K, N51, N53)
IMPORTANT: Read and comply with notes on protection against
electrostatic damage (ESD
protection).
Necessary preliminary tasks:
Read out fault memory of DME control unit; if necessary, work through
test schedules
If necessary, remove radiator cover
Unlock plug (1) and remove. Release bolt.
R
