HEATER AND A/C UNIT, REMOVING AND INSTALLING, "High" A/C SYSTEM, PR NUMBER 9AH/ 9AQ: Installing

Install in reverse order of removal and note the following:

-- Check the grommet -H- for the coolant lines and the rubber bushing -A- for the correct seating and damage.

Courtesy of AUDI OF AMERICA, LLC

-- Check foam seals -F and G- on the condensation water drains for damage and proper seating.

-- Check the condensation water drain for damage and debris.

-- Check both openings -arrows- for the condensation water drains. They must not be closed.

• The condensation water must be able to flow unobstructed out of the condensation water drain.

-- Check the refrigerant line connection -E- and the refrigerant lines -B- for debris and damage.

-- Replace the O-ring seals -C-. Refer to the Parts Information for the version.

-- Coat the O-ring seals lightly with refrigerant oil before installing. Refer to REFRIGERANT CIRCUIT SEALS .

-- Check the retaining plate that holds refrigerant lines and threaded stud -D- in place for secure seating.

• Grommets -B-, -C- and -F- are only present in vehicles with an air distribution housing. They may not be installed in vehicles with a rear heater and A/C unit.
• If a grommet -F- is installed in one of the two openings for the condensation water drains in a vehicle with a rear heater and A/C unit or if these opening are closed from the bottom, for example by underbody sealant, condensation water cannot flow out of the vehicle. Refer to CONDENSATION WATER DRAIN HOSE, CHECKING .

-- Check the ball heads on rear heater and A/C unit -D-, which are inserted in holding points -A-, for damage.

-- Check the outlets at rear heater and A/C unit -D-, which are inserted in air ducts -E-, and air ducts -E-, for damage and contamination.

-- Evacuate and charge the refrigerant circuit. Refer to Refrigerant Circuit or Working with A/C Service Station (1 Of 2) / Working with A/C Service Station (2 Of 2) .

-- Switch the ignition on.

Vehicles with high-voltage system (Audi Q7 e-tron)

-- Initiate the basic setting of the A/C system through the Thermal Management Control Module -J1024- and activate the power-controlled valves using one of the routines stored there. "Charge/flush the refrigerant circuit stop routine" using the Vehicle Diagnostic Tester.

Continuation for All Vehicles

-- Perform a basic setting for the A/C system. Refer to GENERAL INFORMATION AND PROCEDURES - ACTUATORS, REMOVING AND INSTALLING .

-- Start the A/C system after charging the refrigerant circuit. Refer to A/C SYSTEM, STARTING AFTER CHARGING REFRIGERANT CIRCUIT .

-- Bleed the coolant circuit. Refer to COOLANT, DRAINING AND FILLING .