Audi A4: Refrigerant Circuit

Refrigerant Circuit with Expansion Valve and Evaporator

The following illustration shows only the principle of a refrigerant circuit, the design of the refrigerant circuit in the respective vehicle can be found in the vehicle-specific repair manual. Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; Refrigerant Circuit; System Overview - Refrigerant Circuit.

1 - Evaporator

2 - Expansion Valve

3 - Valve for extracting, filling and measuring

4 - Sight glass (not installed in R134a circuits)

5 - Receiver/dryer with dryer

6 - Condenser

7 - A/C Compressor

  Note

Arrows point in direction of refrigerant flow.

Refrigerant Circuit with Restrictor and Reservoir

The following illustration shows only the principle of a refrigerant circuit, the design of the refrigerant circuit in the respective vehicle can be found in the vehicle-specific repair manual. Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; Refrigerant Circuit; System Overview - Refrigerant Circuit.

1 - A/C Compressor

2 - Condenser

3 - Restrictor

4 - Evaporator

5 - Reservoir

  Note

Arrows point in direction of refrigerant flow.

Refrigerant Circuit with an Electrically Driven A/C Compressor (with and without Battery Cooling Module)

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.

- Individuals with electronic/medical life- and health sustaining machines in or on their person cannot perform any work on high-voltage systems. Life- and health sustaining machines are for example pain killer pumps, implanted defibrillators, pacemakers, insulin pumps, and hearing aids.

- Have the high-voltage system de-energized by a qualified person.

There is a Risk of Injury from the Engine Starting Unexpectedly

On electric - hybrid vehicles an active ready mode is difficult to identify. Parts of the body can be clamped or pulled.

- Turn off the ignition.

- Place the ignition key outside of the vehicle interior.

Risk of Damaging the High-Voltage Cables

Misuse can damage the insulation of high-voltage cables or high-voltage connectors.

- Never support objects on the high-voltage cables and the high-voltage connectors.

- Never support tools on the high-voltage cables and the high-voltage connectors.

- Never sharply bend or kink the high-voltage cables.

- When connecting pay attention to the coding of the high-voltage connectors.

• For all procedures on vehicles with high-voltage system pay attention to the additional warning message for these vehicles. Refer to → Chapter "Warnings when Working on Vehicles with High Voltage System".
• If procedures are necessary near components of the high-voltage system "perform a visual inspection of the damage of the high-voltage components and lines". Refer to → Chapter "Performing a Visual Inspection of Damage to High Voltage Components and Cables".
• If work on the components of the high-voltage system is necessity, de-energize the high-voltage system. Refer to → Rep. Gr.93; High-Voltage System, De-Energizing or → Electrical Equipment; Rep. Gr.93; High-Voltage System, De-Energizing.

  Note

The following illustration shows a refrigerant circuit as an example, as it is installed in an Audi Q5 hybrid, for the design of the refrigerant circuit in the respective vehicle refer to the vehicle-specific repair manual. Refer to → Heating, Ventilation and Air Conditioning; Rep. Gr.87; Refrigerant Circuit; System Overview - Refrigerant Circuit.

-Arrows- point in direction of refrigerant flow.

1 - Electrically-Driven A/C Compressor

• With A/C Compressor Control Module -J842- and Electrical A/C Compressor -V470-

2 - Condenser

• With receiver/dryer and dryer cartridge

3 - Service Connection, HP side

4 - Hybrid Battery Refrigerant Shut-Off Valve 1 -N516-

• Only for vehicles with a battery cooling module for the Hybrid Battery Unit -AX1-.

  Note

The Hybrid Battery Refrigerant Shut-Off Valve 1 -N516- is activated, for example, if it is necessary to cool the battery and no cooling is desired in the passenger compartment (open without activation).

5 - Expansion Valve

• On the evaporator in the A/C system

6 - Evaporator

• Evaporator in the A/C System

7 - Expansion Valve with Hybrid Battery Refrigerant Shut-Off Valve 2 -N517-

• On the evaporator in the battery cooling module
• Only for vehicles with a battery cooling module for the Hybrid Battery Unit -AX1-.

  Note

The Hybrid Battery Refrigerant Shut-Off Valve 2 -N517- is activated if it is necessary to cool the battery (closed without activation).

8 - Evaporator

• Evaporator in the battery cooling module
• Only for vehicles with a battery cooling module for the Hybrid Battery Unit -AX1-.

9 - Service Connection, LP Side

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