Audi A4 Owners & Service Manuals

Audi A4: Refrigerant Circuit, Flushing

  Note

  • In the case of vehicles on which the refrigerant lines have no threads for connection of Adapter Set -1785-. Use for example a flushing gun with rubber end piece or an adapter from the Refrigerant Circuits Adapter Set 1 -VAS6338/1- for blowing through the individual components. When using a flushing gun with rubber end piece, take special care not to damage the connections (crushing or scratching).
  • Evaporator is to be flushed via the connection for low-pressure pipe (large diameter) after removing expansion valve or removing restrictor.
  • Always clean (flush or blow) components in direction opposite to refrigerant flow.
  • Check expansion valve and replace if dirty or corroded.
  • Locate any components on which dark, sticky deposits cannot be removed with compressed air and either clean (flush) them using refrigerant R134a or replace them.
  • Thin, light grey deposits on the inside of pipes do not impair the function of the components.
  • After flushing, always replace receiver/dryer or reservoir and restrictor. Replace the dryer cartridge on condensers that have one installed in the integrated receiver/dryer.
  • If the receiver/dryer or dryer cartridge is integrated in the condenser, then they cannot be replaced separately and the condenser must be replaced. Refer to the Parts Catalog and → Heating, Ventilation and Air Conditioning; Rep. Gr.87; System Overview - Refrigerant Circuit (vehicle-specific repair manual).
  • Receivers/dryers where it is possible to replace the dryer cartridge have an additional filter, which must also be replaced with the dryer cartridge.

After Blowing through the Refrigerant Circuit:

- Replace these components depending on equipment (restrictor and reservoir, expansion valve and receiver/dryer or dryer cartridge). Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; System Overview - Refrigerant Circuit (vehicle-specific repair manual) and the Parts Catalog.

- Replace the A/C compressor, depending on its condition. Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; A/C Compressor (vehicle-specific repair manual) and Parts Catalog or drain the rest of the refrigerant oil still inside the removed A/C compressor (replace the refrigerant circuit components) and will new refrigerant. Refer to → Chapter "Refrigerant Circuit Components, Replacing" and → Chapter "Approved Refrigerant Oils and Capacities" (Approved Refrigerant Oils and Capacities).

  Note

  • There is a defined and prescribed amount of refrigerant oil in the replacement compressor. If the vehicle has two evaporators, then there refrigerant circuit requires a specific quantity of refrigerant oil. Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; System Overview - Refrigerant Circuit (vehicle-specific repair manual) and → Chapter "Approved Refrigerant Oils and Capacities". (Approved Refrigerant Oils and Capacities).
  • If the A/C compressor is not be replaced, the quantity of refrigerant oil in the A/C compressor must be topped off to the prescribed capacity (tilt the refrigerant oil out and refill the prescribed quantity into the A/C compressor or refrigerant circuit). Refer to → Chapter "Refrigerant Circuit Components, Replacing" (replacing refrigerant circuit components) and → Chapter "Approved Refrigerant Oils and Capacities". Approved Refrigerant Oils and Capacities).

- Reassemble the refrigerant circuit completely. Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; System Overview - Refrigerant Circuit (vehicle-specific repair manual).

- Evacuate and recharge the refrigerant circuit according to specification. Refer to → Chapter "Refrigerant Circuit, Discharging with Service Station" and → Chapter "Refrigerant Circuit, Charging with Service Station".

- Start up A/C system according to specification. Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; Refrigerant Circuit; A/C System, Starting Operation after Filling Refrigerant Circuit (vehicle-specific repair manual) and → Chapter "A/C System, Operating after Charging".

    READ NEXT:

     Refrigerant Circuit, Cleaning (Flushing), with Refrigerant R134a

     General Information

    Vehicles with a High Voltage System (Hybrid Vehicles) Extremely Dangerous Due to High-Voltage The high-voltage system is under high-voltage. Death or serious bodily injury by electric shock. - I

     Flushing Circuit Block Diagrams

      Note The arrows in the following illustrations show the direction of refrigerant flow during flushing (refrigerant flows in opposite direction of flow when Air Conditioning (A/C) system is

    SEE MORE:

     Sunroof Frame, Removing and Installing

    Sunroof Frame, Removing and Installing, Sedan   Caution This procedure contains mandatory replaceable parts. Refer to component overview and parts catalog prior to starting procedure. Mandatory Replacement Parts Foam Seal - for Sunroof Frame To complete the procedure, a second technician

     Connector Housings and Connectors, Repairing

    Connector Housings and Connectors, Repair Information   Note Observe general notes for repairs on the vehicle electrical system. Refer to → Chapter "Vehicle Electrical System, General Repair Information". Allocation of crimp contacts with correct fit to connector housing is perfo

    © 2019-2024 Copyright www.audia4b9.com