Running A/C System After Installing Compressor

Running A/C System After Installing Compressor

- After installing a new compressor or filling the compressor with new refrigerant oil (e.g. after flushing the refrigerant circuit), manually rotate the compressor approximately 10 revolutions before staring the engine for the first time (prior to installing the belt or before tightening the driveshaft) to prevent damage to the compressor.

- Start the engine first after reconnecting the refrigerant circuit.

- If possible start engine only with a filled refrigerant circuit.

• Different compressors, depending on the country version, production time, and the engine. Refer to => [ Refrigerant Circuit ] Refrigerant Circuit .

• The compressor is continuously driven (by belt pulley or via driveshaft from engine), it has no A/C clutch:

• The compressor has an "internal oil circuit" to ensure the compressor is not damaged when refrigerant circuit is empty. Prerequisite for the internal lubrication is residual refrigerant oil in compressor.

• The engine may only be started when the refrigerant circuit is installed correctly. If for example the refrigerant lines are not connected to the compressor and the engine is started then the compressor may be destroyed by the build-up of internal heat.

• A/C Compressor Regulator Valve (N280) is not activated when the refrigerant circuit is empty and the compressor idles with the engine. As there is no refrigerant in the circuit the oil required to lubricate is not fed to the compressor. To prevent damage to the compressor the compressor is lubricated by an "internal oil circuit".

• If it is necessary to start the engine with a discharged refrigerant circuit:

• - Refrigerant circuit must be completely assembled.

• - At least one quarter of refrigerant oil specified for this refrigerant circuit must be in the compressor.

• - Engine speed should not exceed 2500 RPM.

• - The engine should only run as long as absolutely necessary

Note the following when starting engine for first time after filling refrigerant circuit:

- Start the engine with the compressor switched off ("Econ" mode) and wait until the idling speed stabilizes.

- Open instrument panel vents.

- Set temperature preselect for driver's and front passenger's side to "Low" on A/C control head Climatronic Control Module (J255).

- Switch compressor on ("Auto" mode) and allow engine to run for 5 minutes at idling speed.