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A/C Compressor, Removing And Installing: Installing

Install in reverse order of removal and note the following:

-- Coat the new seals with refrigerant oil before installing.

NOTE:

If the A/C compressor is replaced, it cannot be clearly determined how much refrigerant oil is in the A/C compressor. Due to this reason, read the information about replacing the A/C compressor. Refer to COMPONENTS, REPLACING R134a or COMPONENTS, REPLACING 1234YF .

-- If the A/C compressor is replaced, check the ribbed belt for damage and replace if necessary. Refer to RIBBED BELT, REMOVING AND INSTALLING 1.4L or RIBBED BELT, REMOVING AND INSTALLING 1.8L, 2.0L .

-- Thoroughly clean the contact surfaces on the A/C compressor and bracket.

-- Pay attention to the correct seating of the alignment sleeves -1- in the A/C compressor -2-.

Fig 1: Identifying A/C Compressor
GWWN87-11346Courtesy of AUDI OF AMERICA, LLC
NOTE:

Make sure the alignment sleeves are seated correctly and the contact surfaces are clean. Incorrectly installed alignment sleeves and dirty or damaged contact surfaces can cause alignment irregularities between the A/C compressor and engine. Alignment irregularities over operating time cause damage to the A/C compressor.

If the A/C compressor is replaced due to certain complaints (for example, internal damage), the refrigerant circuit must be flushed. Refer to A/C System - with Refrigerant R134a.

There is an unspecified amount of refrigerant oil in the removed A/C compressor, so therefore pay attention to the information on replacing the A/C compressor. Refer to A/C System, General Information .

For A/C systems with Refrigerant R1234yf

If the A/C compressor was replaced, the following table says if the refrigerant circuit must be flushed before the new A/C compressor is installed.

If flushing is necessity depends on the method of delivery and the refrigerant oil used before this.

  Replacement A/C compressor method of delivery
Denso Mahle/Delphi Sanden
Method of delivery of A/C compressors installed in the vehicle Denso Do not Flush Flushing Flushing
Mahle/Delphi Flushing Do not Flush Do not Flush
Sanden Flushing Do not Flush Do not Flush

-- If the table states that a refrigerant circuit flush is required. Refer to REFRIGERANT CIRCUIT, CLEANING 1234YF .

Continuation for All Vehicles

CAUTION:

Risk of damaging the A/C compressor. Refrigerant oil may accumulate in the compression chamber of the removed A/C compressor.

- After installing a new A/C compressor or filling with fresh refrigerant oil, turn the A/C compressor 10 times by hand before installing the ribbed belt.

Vehicles with Refrigerant R134a

-- Fill the refrigerant circuit. Refer to Working with A/C Service Station .

-- Put the A/C system into operation after filling. Refer to A/C SYSTEM, OPERATING AFTER CHARGING R134A .

Vehicles with Refrigerant R1234yf

-- Fill the refrigerant circuit. Refer to Working with A/C Service Station .

-- Put the A/C system into operation after filling. Refer to A/C SYSTEM, OPERATING AFTER CHARGING 1234YF .

Procedure when Installing a New A/C Compressor

NOTE:

If the A/C compressor is shipped for warranty claims, the extracted refrigerant quantity must be documented and the claim must be included. Refer to the Parts Information.

Read the information for starting the A/C system after installing the A/C compressor. Refer to Refrigerant R134a Servicing or COMPONENTS, REPLACING 1234YF .

-- Run the A/C compressor for the first time  using the Vehicle Diagnostic Tester.