Warning! The air conditioning system is under high pressure. Do not attempt to loosen any connections or remove system parts without first releasing the system. The refrigerant must be removed from the system in a specialized workshop (the type of refrigerant used is listed in Specifications). Even after the system has discharged, wear protective glasses when performing any operations on the system.
In order for the air conditioning system to function properly, it is necessary to regularly perform the following operations:
- Check the condition of the drive belt (see Section Checking the condition of multi-rib belts for auxiliary drive units). If excessive wear or damage is detected, the belt must be replaced (see Chapter Engine);
- Check the condition of the system pipes. Inspect them for cracks, swelling and seals. Also inspect the nipple connections for signs of leaks. If signs of wear, damage or leaks are found, replace the damaged pipe;
- Inspect the surface of the heat exchanger located in front of the radiator of the cooling system. If you find dirt on the fins, insects, etc., clean the surface of the heat exchanger with a special brush or compressed air.
Caution! When using compressed air, wear safety glasses!
- Make sure the evaporator drain tube is not clogged. When the air conditioner is on, clean water should flow from this tube. To check if the tube is clean, place a sheet of paper under the evaporator and turn on the air conditioner. After a certain period of time, traces of water should appear on the sheet.
Turn on the air conditioner at least once a month (even in winter). If you do not use the air conditioner for a long time, it may cause the seals to fail.
Due to the complexity of the system, diagnostics and repairs must be performed at a service station.
(Material created based on the website: mercedesman.ru)
The most likely cause of a decrease in system efficiency is a lack of refrigerant. If you notice a sharp decrease in system efficiency, check the amount of refrigerant in the system as follows.
Warm up the engine to operating temperature.
Use the switch to select the lowest supply air temperature. Turn on the highest fan speed. Open the doors (so that the system does not turn off after reaching the required temperature in the cabin).
When the compressor is turned on, its clutch should make an audible click, and the central part of the clutch should rotate. Touch the inlet and outlet pipes of the compressor. One of them should be cold, the other - hot. If you do not feel the difference, the system is faulty. This can be caused by both a lack of refrigerant and something else. To eliminate the malfunction, contact a service station.