Heating and A/C Unit
Heating and A/C Unit
Special tools, testers and auxiliary items required
• Drip Tray For Shop Crane (VAS 6208)
• Hose Clamps Up To 40 mm Diameter (3093)
• A/C Service Station (ROB 134APF)
• Rinsing Device For Refrigerant Circuits (VAS6337/1)
• Torque Wrench (V.A.G 1331)
• Compressed air gun, commercially available
Removal
• Extract the refrigerant using the (ROB 134APF).
• Environmentally hazardous draining of refrigerant is an offense punishable by law.
• To improve accessibility, additional components, such as the engine cover must be removed (depending on engine version).
- Extract refrigerant using, for example, (ROB 134APF) , only then open the refrigerant circuit. Refer to => [ Specialized Refrigerant Circuit Repairs ] Overhaul.
- Remove the instrument panel.
- If the vehicle has a steel subframe, then remove the subframe. The tunnel support is welded to the steel tube on these vehicles.
- Remove the right and left footwell channels (on vehicles where it is not necessary to remove the subframe). Refer to => [ Rear Footwell Channel ] Rear Footwell Channel.
- Place (VAS 6208) under the engine.
- Mark the coolant hoses - 1 -.
There is a danger of ice-up.
Refrigerant leaks out if refrigerant circuit is not discharged.
Refrigerant must be extracted before opening the refrigerant circuit. If refrigerant circuit is not opened within 10 minutes after extracting, pressure may build up in refrigerant circuit by renewed evaporation. Extract refrigerant once more.
- Clamp the coolant hoses - 1 - using the (VAS 3093) and remove the coolant hoses from the heater core.
- Connect a section of hose - A - to the upper connection.
- Hold a container - B - under the lower connection - C -.
- Using a compressed air gun, carefully blow residual coolant out of heater core at heater core connection.
Only for vehicles with a heat shield in front of the expansion valve
- Remove the nut - 1 - (6 ± 0.9 Nm).
- Remove the clamps - 2 - and the heat shield - 3 -.
- From inside the engine compartment, remove the bolts - 1 - from the refrigerant pipes - 2 -.
- Remove the refrigerant pipes from the expansion valve - 3 -.
• Seal the open connections.
• To seal off all open connections on expansion valve, sealing caps from a replacement expansion valve can be used (preventing dirt and moisture from entering the system).
- Cover the carpet inside the passenger compartment with waterproof foil and water absorbing paper.
• When removing the bolts, make note of the lengths and allocation.
1 Screw
• 4.5 ± 0.7 Nm
• On the lower right side on the cable bracket for the heater and air conditioner near the plenum chamber bulkhead.
2 Screws
• 4 ± 0.7 Nm
• Quantity: 2
3 Cable Bracket
4 Heating and A/C Unit
• Removing
- Remove the condensation water hose from the heater and air conditioner. Refer to => [ Condensation Water Drain Hose, Checking ] Testing and Inspection.
- Disconnect the connectors from the heater and air conditioner.
• All cable ties opened or cut during removal must be reinstalled at the same locations during installation.
• The air conditioning wiring harness is removed with the heater and air conditioner.
- Remove the bolts - 7 - and - 5 -.
- Remove the supports - 8 - and - 9 -. Subframe bolts: 9 ± 1.3 Nm. Tunnel bolts: 20 ± 3 Nm.
• If the vehicle has a steel subframe, then remove the subframe. The supports - 8 - and - 9 - are welded to the steel pipe on these vehicles.
- Remove the bolts - 10 - and - 12 - and bracket - 11 -.
- Remove the bolts - 1 - and - 2 - from the cable bracket - 3 -.
• Pull the heater and A/C unit slightly from the bulkhead on the front passenger side in order to be able to access the bolt - 1 -.
• When removing heat unit, make sure the two coolant pipes of the heater core do not get caught and bent or damaged on plenum chamber or noise insulation pan.
• Observe wiring harness, individual electrical wiring connections may get damaged when pulling on harness.
- Remove heating and A/C unit.
• Installing
Installation is carried out in the reverse order while noting the following:
• A second technician is necessary to install the heater.
• Tighten the bolts on the subframe first when installing the supports - 8 - and - 9 -.
- When inserting heater, have the second technician guide both coolant pipes to heater core through the seal (from engine compartment).
- Fill the coolant.
- Fill with R134a refrigerant and refrigerant oil.
5 Bracket
6 Subframe
• There are two types of subframes (aluminum and steel). The steel supports are welded to the steel pipe.
7 Screws
• 9 ± 1.3 Nm
8 Right Support
9 Left Support
10 Screws
• 9 ± 1.3 Nm
• Quantity 2
11 Bracket
12 Screws
• 9 ± 1.3 Nm
• Quantity 2
Seal for Heating and A/C unit / engine compartment
• Make sure the seal - A - is installed correctly.