Press Release

Have you had your air-conditioning system flushed today? Garage tip from Behr Hella Service: Professional flushing of the air-conditioning system increases its service life

Lippstadt, July 2007. In the context of repairing an air-conditioning system, ever more vehicle and component manufacturers require that flushing is carried out and documented. This is because a clean system is the fundamental prerequisite for perfect operation and for excluding the possibility of consequential damage. Only in this way can guarantee claims be protected.
If components of the air-conditioning system are defective (for example: an old filter-dryer or compressor damage), it is easy for dirt particles to become distributed throughout the entire refrigerant circuit. Therefore, it is important that before installing new parts, the entire system is flushed. Behr Hella Service offers special flushing sets both for flushing with fluid and for flushing with nitrogen. In the case of flushing with nitrogen, all system components and connection lines are purged with a pressure of approximately twelve bar and dried. The advantage of this method: Low costs for the nitrogen, no disposal costs. In the case of flushing with flushing fluid, the process is carried out using chemical agents. After this, the residues of the flushing agent must be removed from the circuit with the aid of nitrogen, and the entire system must be dried using nitrogen. The high level of effectiveness of the combination of flushing fluid and nitrogen makes these methods essential when replacing a compressor. In the case of the third flushing method, which is advisable, the system components are flushed with the aid of an air conditioning service unit (SECUmobile or SECUsmart from Behr Hella Service) and an additional flushing device with filter and adapters (both are available separately). The advantages of these methods: no costs or disposal costs for the flushing medium, loose dirt particles and oil are removed, and the process is approved by various vehicle manufacturers.

1. In the event of compressor damage, contamination due to metal abrasion must be eliminated
2. Residues of acid arising due to moisture – such as after the air-conditioning system has been open for a long time, for instance after an accident – must be removed
3. Blockages caused by elastomer particles must be flushed out
4. All traces of contaminated refrigerant or refrigerant oils must be removed

• Always flush only the individual components of the circuit
• Dryer, valves and compressor may not be flushed
• After flushing with special, chemical fluid, drying must be carried out using nitrogen
• Every time that an air-conditioning circuit is opened, the replacement of the filter-dryer and the O-rings of the components opened is necessary

A further tip:
The PAO compressor oils from the thermal management experts Behr Hella Service PAO-Oil 68 and PAO-Oil 68 PLUS UV are synthetic oils, which can be used widely in all air-conditioning systems of passenger cars, trucks and agricultural and construction machinery. Behr Hella Service PAO-Oils are not hygroscopic, they do not absorb any moisture and can therefore be stored for a long time even after opening. In addition, they are suitable for all types of refrigerants and are compatible with all lubricants. They have an extensive operating range of -69 °C to +315 °C. Furthermore, the PAO-Oils have a higher cooling performance with lower energy expenditure and reduce compressor noises.

Flushing media und methods