Air Conditioner Maintenance and Precautions (BMW 5 Series E28)

Precautionary measures

The air conditioning system is under high pressure. DO NOT loosen any connections or remove any system components until the system is completely discharged. The air conditioning refrigerant must be properly released into a special container by a qualified technician. The refrigerant used in the system must not come into contact with your skin or eyes, as there is a risk of frostbite. When the refrigerant comes into contact with an open flame, a toxic gas is released. Therefore, smoking while working with refrigerant is extremely dangerous, especially inhaling its vapors from a lit cigarette. Refrigerant has a higher specific gravity than air and can cause suffocation if worked with in a closed area, such as a home garage. Finally, uncontrolled release of refrigerant into nature can cause serious damage to the environment, creating a "greenhouse effect".

Service

To ensure your air conditioner operates at maximum efficiency, the following checks should be performed regularly:

1. Check the drive belt. If it is worn or damaged, replace it (see chapter Routine car maintenance).

2. Check the system hoses. Look for cracks, bulges, hardening and signs of wear. Inspect the hoses and fittings for oil bubbles and leaks. Replace the hoses if any signs of wear, damage or leaks are found.

3. Inspect the condenser fins for trapped leaves, insects, or other debris. Use a fin comb or compressed air to clean the condenser.

4. Make sure the system is properly charged with refrigerant as described below.



5. It is very useful to run the system for about 10 minutes at least once a month, especially in winter. Not using the system for a long time can lead to hardening and subsequent failure of the system seals.

6. Due to the complexity of the air conditioning system and the special equipment required for servicing it, extensive troubleshooting and repair procedures are not included in this manual. However, simple checks and component replacement procedures are provided in this Chapter.

7. The most common cause of poor cooling is low refrigerant charge in the system. If you notice a noticeable decrease in cool air output, the following quick check will help you determine if the refrigerant level in the system is low.

8. Warm up the engine to normal operating temperature.

9. Set the air conditioner temperature switch to the coldest position and the air blower to maximum. Open the doors (to make sure that the air conditioning system does not turn off once it has cooled the interior).

10. When the compressor is on - the compressor clutch will make a noticeable click and its center will start to rotate - touch the pipe located close to the right front frame member, next to the radiator.

11. If you notice a significant drop in temperature, then the refrigerant level is probably normal.

12. If the inlet line is frosted or feels colder than the surface of the accumulator/dehydrator, the refrigerant level is low. The system should only be recharged by a qualified technician.

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