When replacing an air conditioning compressor, it is important to pay attention to important features in order to avoid direct failure of the new air conditioning compressor or consequential damage to the air conditioning circuit. One of these is the correct filling of the new compressor with oil.
Air conditioning compressors from MAHLE are filled with a basic quantity of oil. Regardless of the delivery condition of the air conditioning compressors, the oil filling quantity must always be checked for each air conditioning compressor before installation in the vehicle and corrected in accordance with the manufacturer's specifications and the enclosed documentation. The reason: Many air conditioning compressors are not only used in one vehicle, but in different models and versions. The corresponding oil filling quantity must therefore be adjusted.
1. drain the oil via the drain plug into a clean container and measure the oil quantity.
2 Depending on the manufacturer's specifications, add fresh oil or reduce the amount (observe the oil specification!).
3. Fill the air conditioning compressor with the specified amount of oil (system oil quantity).
4. Install the drain plug with a new seal.
5. belt-driven compressor: stand upright for three minutes (belt pulley pointing downwards).
6. Belt-driven compressor: Turn the belt pulley ten times by hand in the horizontal position.
Important 1: For vehicles with two evaporators, the quantity of oil and refrigerant must always be increased. There are some air conditioning compressor types without a drain plug that do not allow the refrigerant oil to be drained and adjusted. These air conditioning compressors are already supplied with the system quantity of refrigerant oil intended for the vehicle.
Important 2: Do not confuse the safety valve (pressure relief valve) with the drain plug when draining the oil. This is because oil cannot be drained or refilled in this way, even if the valve is removed. As the valve is always located in the high-pressure area of the compressor, it has no connection to the working chamber in which the oil is located.
In some cases, flushing is not necessary when replacing the air conditioning compressor. This applies to an electrical defect, for example. Nevertheless, please note: The system must be clean, leak-proof and filled with the correct amount and specification of compressor oil. If the air conditioning compressor is replaced without flushing, it is particularly important that the amount of oil in the new compressor is reduced to prevent overfilling. Around 50 percent of the compressor oil is in the compressor, the rest is distributed among the other components in the system. If other components are replaced, you must take their percentage share of the total oil quantity into account when filling.
To avoid overfilling the system, you must first drain the oil from the new compressor into a clean container. Pour the oil from the defective compressor into a second container. Use a measuring cup to determine the quantity. This amount of used oil corresponds to the amount of fresh oil that needs to be poured into the new compressor. Do not reuse the oil from the old compressor; you must dispose of it in an environmentally friendly manner.
The unique combination of expert knowledge and comprehensive warranty services makes the MAHLE Compressor Warranty Plus an absolute must for automotive professionals. We provide you with real expert knowledge in a one-day training course. Our air conditioning professionals will give you important practical tips and show you what you need to pay particular attention to in order to professionally replace an air conditioning compressor step by step. The workshop is then automatically registered for the Compressor Warranty Plus for two years.
Complaints from workshops with the MAHLE Compressor Guarantee Plus are guaranteed to be recognized by us. This allows you to make a complaint about defective air conditioning compressors quickly and unbureaucratically and receive a credit note for the air conditioning compressor, other add-on parts and the working time spent as quickly as possible.