A/C Compressor

A/C Compressor

• Depending on time period of production and on engine, compressor construction type may vary. Refer to Electronic Parts Catalog (ETKA).

• At the beginning of production, A/C compressors manufactured by Denso (type 7 SEU 16 or 7 SEU 17) were installed; from MY 2004 A/C compressors by other manufacturers (Delphi, Sanden or Zexel) may also be installed.

• These A/C compressors are available as replacement parts with different oil fill capacities, therefore note capacity on A/C compressor and the exact part number.

• Beginning the production year 2006, the name of the Zexel A/C compressor was changed from Zexel to Valeo.

• Depending on A/C compressor type, different refrigerant oil fill capacities are designated for the refrigerant circuit. The reason for the different oil capacities in the A/C compressor for an otherwise identical refrigerant circuit lies in the design of the A/C compressor itself, note these oil capacities. Too much oil in the circuit leads to high pressures and to a reduction in the system cooling performance, too little oil may lead to lubrication problems in the A/C compressor.

• If a new compressor has been installed or new refrigerant oil has been put into the A/C compressor (e.g. after blowing through the A/C system), the A/C compressor must be turned by hand approximately 10 revolutions. This ensures that the compressor is not damaged when activated.

Removing

- Discharge the refrigerant circuit.

- Disconnect refrigerant lines from A/C compressor. Refer to=> [ A/C Compressor Refrigerant Lines ] A/C Compressor Refrigerant Lines.

• The sequence is different and depends on the engine. On vehicles with a 3.2L MPI engine, the A/C compressor must first be removed from the bracket before refrigerant lines can be removed. It is possible to remove the refrigerant lines with the A/C compressor still installed on 2.0L TFSI vehicles.

- Remove the A/C compressor from the bracket. Refer to => [ Compressor, Removing From Bracket ] Compressor, Removing From Bracket.

Installing

Installation is carried out in the reverse order while noting the following:

Before installing the A/C compressor, refer to => Refrigerant R134a Servicing Removal and Installation.

• Coat the O-ring seals lightly with refrigerant oil prior to installation. Refer to => [ Refrigerant Circuit O-rings ] Refrigerant Circuit O-Rings.

• An uncertain quantity of refrigerant oil remains in a removed A/C compressor. Therefore, observe the notes for replacing the A/C compressor.

• Tightening specifications, refer to => [ Compressor, Removing From Bracket ] Compressor, Removing From Bracket. Attach the refrigerant lines to the A/C compressor. Refer to => [ A/C Compressor Refrigerant Lines ] A/C Compressor Refrigerant Lines.

• Replace the O-rings at the opened connection locations. Refer to => [ Refrigerant Circuit O-rings ] Refrigerant Circuit O-Rings and Electronic Parts Catalog.

- Only start engine after refrigerant circuit has been assembled.

- If a new A/C compressor has been installed or fresh refrigerant oil has been filled into the A/C compressor before installing ribbed belt (for example, after cleaning refrigerant circuit), the A/C compressor must be turned by hand approximately 10 turns. This ensures that the A/C compressor will not be damaged when engine is first started.

- Mount the ribbed belt(s) on the ribbed belt pulley.

- Discharge and fill the refrigerant circuit.

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

• Different A/C compressors, depending on production time period and on engine => [ Refrigerant Circuit Component Overview ] Refrigerant Circuit Component Overview and Electronic Parts Catalog.

• The A/C compressor is always driven by a belt pulley (there is no magnetic clutch).

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

• The engine may only be started when the refrigerant circuit is installed correctly. For example; if the refrigerant lines are not connected to A/C compressor, when the engine is running the A/C compressor may heat up (via internal heat generation) so much that the A/C compressor will be damaged.

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

• To prevent damage, the A/C compressor is lubricated by an internal oil circuit.

• If it is necessary to start the engine with a discharged refrigerant circuit. Refer to => [ A/C System, Operating After Filling Refrigerant Circuit ] Procedures.