Replacement of aircon compressor and other aircon components should be carried out by a fully trained aircon technician using the correct equipment, the below guide is for information only and is not intended as advice for any DIY mechanic to follow!
Old Part Dismantling & Troubleshooting
Remove the failed compressor, and try to determine the cause of the defect. Please bear in mind that, in most cases, failure of the air conditioning system is caused by another component than the compressor itself, which then leads to compressor failure as a result. Before installing the new compressor, the cause of the failure and the defective component must be identified and fixed. When removing the hoses connected to the compressor, please make sure to protect the connections. This is to avoid impurities sticking to the connection during installation of the compressor.
System flushing
The system must be properly flushed using R134a/R1234YF or a specially designed flushing solution. Nissens strongly recommends using a specially designed flushing solution, due to its higher efficiency and chemical advances. After flushing, make sure that no refrigerant or flushing liquid is left in the system, and dry the circuit using nitrogen, if necessary. It is not considered advisable to reuse any refrigerant removed from the circuit, since the used refrigerant is most likely contaminated with impurities from the replaced compressor.
Condenser
If the replaced compressor has left impurities, residues or particles in the AC system, the condenser, if it has parallel flow or multi flow, must be replaced as thorough cleaning/flushing of this condenser type is not possible. If the polluted condenser is not replaced, it will cause the replacement compressor to break down.
Other condenser types: Make sure the condition of the condenser is so that the performance is sufficient to maintain the proper temperature in the system. A non-conforming condenser may cause overheating of the compressor.
Other parts replacement
Then complete installation of replacement parts
dryer/accumulator, expansion valve or orifice tube.
Compressor lubrication
Check that the level of pre-filled oil is in accordance with the vehicle manufacturer´s instructions. If extra filling is necessary, make sure to use oil of the same viscosity as indicated in the vehicle manufacturer´s instructions.
After checking or filling the oil, please turn the clutch on the compressor 10 times to distribute the oil inside.
Avoid impurities
When mounting the compressor, do not remove the safety caps in the connection holes before the hoses are connected. This is to avoid that impurities enter the system during mounting of the compressor.
O-rings and seals
New o-rings or gaskets must be applied for all disassembled serviced connections.
When the compressor has been installed, tube connections must be connected using new sealant/o-rings.
System charge
Fill or re-charge the refrigerant cycle with the prescribed amount of refrigerant according to instructions. Use only refrigerant prescribed by the car manufacturer!
Driving Belt
Check the belt tightener, and make sure the belt is aligned correctly when installed.
Inspect the V-belt (fan belt) and replace it if any signs of tear or reduced strength. A defective V-belt (fan belt) can cause serious damage to the compressor as well as to the engine.
Final Inspection
After installing the compressor, you may be required to clear the fault indication in the central control unit, otherwise the compressor will not receive the proper signal from the central control unit and will fail to start.
Start vehicle and leave it running at idling speed for a couple of minutes – then the vehicle can operate at usual working level.
Nissens’ warranty only covers claims related to proven manufacture defects. If any of the above points are not performed/documented, Nissens shall not be obliged to cover any product/expenses related to a breakdown of the compressor! (Also applies to compressors from other manufacturers that we supply)