Detaching and attaching refrigerant lines on air conditioner compressor - vehicles with 8-cyl. TDI engine — AUDI

🧭 Before you start

Fits: Audi A8 D4 (4H, 2010–2017)

• Opens: refrigerant (A/C)

Don't miss

• Seal the open pipes and connections at the air conditioner compressor with suitable caps (to prevent the ingress of dirt and moisture).
• Risk of damage to refrigerant lines and hoses.Do not stretch, kink or bend refrigerant lines and hoses. — Replace the O-rings (D) and (E); for version refer to Electronic parts catalogue
• Lubricate O-rings lightly with refrigerant oil before installing Refrigerant circuit seals.
• Do not use O-rings from caps of replacement compressor connections.Make sure O-rings are positioned correctly in groove (G) of corresponding refrigerant line.

🔩 Torque settings

Values can differ between engine variants — check the code stamped on your block.

ℹ️ Always cross-check the exact figure against your vehicle's factory manual before final tightening — a wrong torque can damage the engine. These values are extracted from workshop data and may not cover every variant or revision.

📋 Procedure

1. ⚠ Different refrigerant and refrigerant oil capacity for vehicles with an 8-cyl. TDI engineOn account of the installation position of the air conditioner compressor (at the top of the engine), the quantity of refrigerant oil differs on vehicles with an 8-cyl. TDI engine from the quantity indicated on the rating plate of the air conditioner compressor Air conditioner with refrigerant R134a87Capacities for refrigerant R134a, refrigeration oil and approved refrigeration oils. — Switch off ignition.
2. Discharge refrigerant circuit Air conditioner with refrigerant R134a87Refrigerant circuit.
3. Detach engine cover panel (arrows).
4. Remove bolts (A).
5. Detach refrigerant lines (B) and (C). [Note: Seal the open pipes and connections at the air conditioner compressor with suitable caps (to prevent the ingress of dirt and moisture).]

6. ⚠ Risk of damage to refrigerant lines and hoses.Do not stretch, kink or bend refrigerant lines and hoses. — Replace the O-rings (D) and (E); for version refer to Electronic parts catalogue
7. Check guide ring (F) at connections of both refrigerant lines (B) and (C) for damage.
8. Clean connections of refrigerant lines and connections at air conditioner compressor and check them for damage.
9. Lubricate O-rings lightly with refrigerant oil before installing Refrigerant circuit seals.
10. Insert appropriate O-ring ((D) and (E)) in groove (G) at connections of both refrigerant lines (B) and (C). [Note: Do not use O-rings from caps of replacement compressor connections.Make sure O-rings are positioned correctly in groove (G) of corresponding refrigerant line.]
11. Insert both refrigerant lines (B) and (C) in corresponding connections at air conditioner compressor.
12. Tighten bolts (A) to 9 Nm (bolts with M6 thread) / 25 Nm (bolts with M8 thread). [Note: After attaching the refrigerant lines to the air conditioner compressor (and after installing the compressor) check the routing of the lines. They must be inserted in the brackets provided and must not make contact with other components.] — 9 Nm (6.6 lb-ft)
13. Evacuating and charging refrigerant circuit Air conditioner with refrigerant R134a87Refrigerant circuit.
14. Re-install remaining components (removed earlier).
15. Switch on ignition.
16. Interrogate the event memory of the operating and display unit, Climatronic control unit J255 and erase any faults displayed. [Note: Also observe notes on starting up air conditioner after charging Air conditioner with refrigerant R134a87General information on air conditioner.]

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