Refrigerant and Coolant Circuits Components and Plenum Chamber Water Drains
Refrigerant and Coolant Circuits Components and Plenum Chamber Water Drains
1 Refrigerant Line With Inner Heat Exchanger With Quick-Release Couplings
• Installed in the area of the A-pillar under the left fender.
• Removal and installation, refer to => [ Refrigerant Lines With Inner Heat Exchanger ] Refrigerant Lines With Inner Heat Exchanger.
• Disconnecting, refer to => [ Refrigerant Lines, Disconnecting from Quick-Release Couplings and Connecting ] Refrigerant Lines, Disconnecting from Quick-Release Couplings and Connecting.
The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty.
• In this refrigerant line, liquid warm refrigerant from the high pressure side is released into the low pressure side as flowing vaporous refrigerant energy. This increases the cooing efficiency of the A/C system.
2 Outlet Of The Refrigerant Line To The Evaporator In The Rear A/C Unit
• Only present on vehicles with a rear heating & A/C unit (optional equipment).
• Bolts of the connection points must only be loosened when refrigerant circuit has been discharged.
3 Plenum Chamber Water Drains
• Two water drains are installed on the left and right in the plenum chamber.
• Removal and installation, refer to => [ Plenum Chamber Water Drain ] Service and Repair.
4 Refrigerant Lines To The Evaporator In The Rear A/C Unit
• Only present in vehicles with a rear A/C unit (optional equipment).
5 Connection Of The Coolant Pipes To The Heater Core For The Heater In The Rear A/C Unit
• Remove and install the coolant hoses, refer to => [ Rear Heater Core ] Rear Heater Core.
• Refer to => [ Coolant Circuit, Bleeding ] Coolant Circuit, Bleeding.
6 Rear Expansion Valve
• Only present in vehicles with a rear A/C unit (optional equipment).
• For the evaporator in the rear A/C unit (installed on the underbody of the vehicle in the area of the center tunnel).
• Bolts of the connection points must only be loosened when refrigerant circuit has been discharged.
• Removal and installation, refer to => [ Rear Expansion Valve ] Rear Expansion Valve.
• Ensure the correct allocation by referring to the Electronic Parts Catalog.
• Check the function, refer to => [ A/C Unit, Checking Cooling Output ] A/C Unit, Checking Cooling Output.
• After the A/C compressor is switched off in this vehicle, it may take a relatively long time for the pressure on the high pressure side to decrease (the expansion valve(s) is/are cold, the pressure on the low pressure side increases quickly after deactivation, the expansion valve(s) closes/close and the refrigerant can only flow slowly to the low pressure side).
7 Coolant Connections to the Heater Core For the Heater In the Front A/C Unit
• Remove and install the coolant hoses, bleed the coolant circuit. Refer to => [ Heater Core With Front A/C Unit Installed ] Heater Core With Front A/C Unit Installed.
8 Refrigerant Lines To The Front Expansion Valve
• Disconnect and connect the refrigerant line, refer to => [ Front Expansion Valve Refrigerant Lines, Disconnecting ] Front Expansion Valve Refrigerant Lines, Disconnecting.
• Removal and installation, refer to => [ Front Expansion Valve ] Front Expansion Valve.
• Bolts of the connection points must only be loosened when refrigerant circuit has been discharged.
9 A/C Compressor
• Different arrangement, depending on the engine.
• TDI engine, refer to => [ A/C Compressor From Bracket ] A/C Compressor from Bracket.
• For 6 cylinder gas engines or an 8-cylinder FSI / TFSI engine, the A/C compressor can only be removed from the bracket if the refrigerant circuit has been discharged. Refer to 6 cylinder gasoline => [ Compressor ] Compressor, 8 cylinder FSI => [ Compressor ] Compressor or 8 cylinder TFSI => [ Compressor ] Compressor.
• For 12 cylinders, the A/C compressor can only be removed from the bracket if the refrigerant circuit has been discharged. Refer to => [ A/C Compressor from Bracket ] A/C Compressor from Bracket.
• Additional information, refer to => [ Refrigerant Circuit Components Overview ] Refrigerant Circuit Components Overview.
10 A/C Compressor Regulator Valve (N280)
• Different arrangement of the A/C compressor, depending on the engine.
• For checking activation and functionality, refer to => [ A/C Compressor Regulator Valve (N280), Checking Switch-On Signal ] A/C Compressor Regulator Valve (N280), Checking Switch-On Signal.
• The A/C compressor regulator valve is activated by the vehicle electrical system control module (J519) , from => [ A/C Compressor Regulator Valve (N280), Checking Switch-On Signal ] A/C Compressor Regulator Valve (N280), Checking Switch-On Signal. The Climatronic control module (J255) , first transmits the request to activate the A/C compressor regulator valve via the data bus to the data bus on board diagnostic interface (J533). From there, the request is transmitted to the vehicle electrical system control module. Check using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function and.
11 Condenser With Fluid Reservoir
• May only be removed when refrigerant circuit has been discharged; bring vehicle to a workshop that has the necessary tools and in which the work can be performed accordingly by qualified personnel.
• There are different versions depending on the vehicle equipment level. Refer to the Electronic Parts Catalog.
• Refrigerant lines, removing and installing, refer to => [ Condenser Refrigerant Lines ] Condenser Refrigerant Lines.
• Fluid reservoir is a component of the condenser.
• The dryer cartridge installed in the fluid reservoir can be replaced as an individual part, refer to => [ Dryer Cartridge ] Dryer Cartridge.
• Removal and installation, refer to => [ Condenser ] Condenser.
• Drier cartridge, removal and installation, refer to => [ Dryer Cartridge ] Dryer Cartridge.
12 A/C Pressure/Temperature Sensor (G395)
• Removal and installation, refer to => [ A/C Pressure/Temperature Sensor (G395) ] A/C Pressure/Temperature Sensor (G395).
• To check the signal use the Vehicle Diagnostic Tester in the "Guided Fault Finding" function.
• The A/C pressure/temperature sensor exchanges information with the vehicle electrical system control module (J519) via a local data bus, refer to => [ A/C Pressure/Temperature Sensor (G395), Checking Pressure Signal ] A/C Pressure/Temperature Sensor (G395), Checking Pressure Signal. The vehicle electrical system control module then transmits the determined measured values to the data bus on board diagnostic interface (J533). They are then relayed via the data bus to the Climatronic control module (J255). Check using the Vehicle Diagnostic Tester in the "Guided Fault Finding" function and.
13 Refrigerant Line With Inner Heat Exchanger With Quick-Release Couplings
• Installed in the area under the left headlamp.
• Removal and installation, refer to => [ Refrigerant Lines With Inner Heat Exchanger ] Refrigerant Lines With Inner Heat Exchanger.
• Disconnecting, refer to => [ Refrigerant Lines, Disconnecting from Quick-Release Couplings and Connecting ] Refrigerant Lines, Disconnecting from Quick-Release Couplings and Connecting.
The quick-release coupling connectors may be unlocked and opened only if the refrigerant circuit is empty.
• In this refrigerant line, liquid warm refrigerant from the high pressure side is released into the low pressure side as flowing vaporous refrigerant energy. This increases the cooling efficiency of the A/C system.
14 Low Pressure Side Service Connection
• For measuring and discharging the refrigerant circuit.
• Cap and seal, always install.
• There are different versions (with primary sealing valve or with a Schrader valve) depending on the refrigerant line, characteristics.
15 High Pressure Side Service Connection
• For measuring and discharging the refrigerant circuit.
• Installed under a door in the plenum chamber cover.
• Cap and seal, always install.
• There are different versions (with primary sealing valve or with a Schrader valve) depending on the refrigerant line, characteristics.