System Overview - Refrigerant Circuit With Expansion Valve And Receiver/Dryer

HD  = High Pressure Side

ND  = Low Pressure Side

Fig 1: Refrigerant Circuit With Expansion Valve And Receiver/Dryer Component Locations

Courtesy of AUDI OF AMERICA, LLC

1. A/C Compressor Regulator Valve -N280-
2. A/C Compressor
3. Belt Pulley
   • Depending on the version a A/C Clutch -N25- is installed in the belt pulley. Refer to Refrigerant CircuitRefrigerant Circuit with Ignition Switched on, Checking PressureRefrigerant Circuit Pressures and TemperaturesRefrigerant Circuit, CleaningRefrigerant, Filling in ReservoirRefrigerant Circuit, ChargingRefrigerant Circuit, EvacuatingRefrigerant Circuit, DischargingRefrigerant Gas Analysis, PerformingRefrigerant Circuit, Flushing with Compressed Air or NitrogenRefrigerant Circuit, Cleaning Process Refrigerant Circuit, Cleaning Refrigerant Circuit, Finding Leaks using Electronic Leak Detector Refrigerant Temperature Sensor Refrigerant Circuit Connections with Valve for Switches Refrigerant Circuit Pipes and Hoses Refrigerant Line with Inner Heat Exchanger Refrigerant Shut-Off Valves Refrigerant Circuit Layout and Function Refrigerant Circuit Refrigerant Circuit Components, ReplacingRefrigerant R134a Vapor Pressure Table (vehicle-specific repair information).
   • Depending on the version instead of the belt pulley a drive unit can also be present. Refer to Refrigerant CircuitRefrigerant Circuit with Ignition Switched on, Checking PressureRefrigerant Circuit Pressures and TemperaturesRefrigerant Circuit, CleaningRefrigerant, Filling in ReservoirRefrigerant Circuit, ChargingRefrigerant Circuit, EvacuatingRefrigerant Circuit, DischargingRefrigerant Gas Analysis, PerformingRefrigerant Circuit, Flushing with Compressed Air or NitrogenRefrigerant Circuit, Cleaning Process Refrigerant Circuit, Cleaning Refrigerant Circuit, Finding Leaks using Electronic Leak Detector Refrigerant Temperature Sensor Refrigerant Circuit Connections with Valve for Switches Refrigerant Circuit Pipes and Hoses Refrigerant Line with Inner Heat Exchanger Refrigerant Shut-Off Valves Refrigerant Circuit Layout and Function Refrigerant Circuit Refrigerant Circuit Components, ReplacingRefrigerant R134a Vapor Pressure Table (vehicle-specific repair information).
4. Pressure Relief Valve
5. Refrigerant Pressure Sensor
   • Vehicle-specific version. Refer to Refrigerant CircuitRefrigerant Circuit with Ignition Switched on, Checking PressureRefrigerant Circuit Pressures and TemperaturesRefrigerant Circuit, CleaningRefrigerant, Filling in ReservoirRefrigerant Circuit, ChargingRefrigerant Circuit, EvacuatingRefrigerant Circuit, DischargingRefrigerant Gas Analysis, PerformingRefrigerant Circuit, Flushing with Compressed Air or NitrogenRefrigerant Circuit, Cleaning Process Refrigerant Circuit, Cleaning Refrigerant Circuit, Finding Leaks using Electronic Leak Detector Refrigerant Temperature Sensor Refrigerant Circuit Connections with Valve for Switches Refrigerant Circuit Pipes and Hoses Refrigerant Line with Inner Heat Exchanger Refrigerant Shut-Off Valves Refrigerant Circuit Layout and Function Refrigerant Circuit Refrigerant Circuit Components, ReplacingRefrigerant R134a Vapor Pressure Table .
6. Condenser (with Receiver/Dryer)
7. Receiver/Dryer
   • Installed on a condenser or in the condenser. Refer to Refrigerant CircuitRefrigerant Circuit with Ignition Switched on, Checking PressureRefrigerant Circuit Pressures and TemperaturesRefrigerant Circuit, CleaningRefrigerant, Filling in ReservoirRefrigerant Circuit, ChargingRefrigerant Circuit, EvacuatingRefrigerant Circuit, DischargingRefrigerant Gas Analysis, PerformingRefrigerant Circuit, Flushing with Compressed Air or NitrogenRefrigerant Circuit, Cleaning Process Refrigerant Circuit, Cleaning Refrigerant Circuit, Finding Leaks using Electronic Leak Detector Refrigerant Temperature Sensor Refrigerant Circuit Connections with Valve for Switches Refrigerant Circuit Pipes and Hoses Refrigerant Line with Inner Heat Exchanger Refrigerant Shut-Off Valves Refrigerant Circuit Layout and Function Refrigerant Circuit Refrigerant Circuit Components, ReplacingRefrigerant R134a Vapor Pressure Table (vehicle-specific repair information).
   • With dryer cartridge
8. Service Connection - High Pressure Side
   • With closure cap
9. Refrigerant Line with Inner Heat Exchanger
10. Front Expansion Valve
11. Front Evaporator
    • Evaporator in the front heater and A/C unit (installed under the instrument panel)
12. Service Connection - Low Pressure Side
    • With closure cap
13. Rear Expansion Valve
    • Only present in vehicles with a rear A/C unit (optional equipment)
14. Rear Evaporator
    • Only present in vehicles with a rear A/C unit (optional equipment)