Heat Exchanger
Heat Exchanger
Special tools, testers and auxiliary items required
• Drip Tray For VAS 6100 (VAS 6208)
• Hose Clamps Up To 40 mm (VAS 3093)
• Compressed air gun, commercially available
Removing
- Remove the bulkhead inside the plenum chamber.
- Place the (VAS 6208) under the engine.
Contact with hot engine coolant can cause severe scalding.
Coolant temperature can be above 100 °C with a warm engine. The cooling system is under pressure.
If necessary, reduce pressure and temperature before repairs.
- Clamp off the coolant hoses - 1 - using the (VAS 3093) and remove the coolant hoses from the heat exchanger.
- Connect a section of hose - A - to the upper connection on the heater core.
- Hold a container - B - under the lower connection - C -.
- Using a compressed air gun, carefully clear out any coolant still inside the heat exchanger into the container - B -.
- Remove the bolt (6 mm inner hex) - 1 - from the connection flange between the heat exchanger connections.
• This allows the coolant pipes to move for removing the heater core.
- Remove driver side footwell trim.
- Remove the left footwell vent, refer to => [ Left Footwell Vent ] Left Footwell Vent.
- Remove the bolts - 1 - and remove the heat exchanger trim.
- Cover the carpet the in area under heat exchanger with waterproof foil and water absorbing paper.
- Open the clamps - A - and remove the coolant pipes from the heat exchanger.
- Remove the heat exchanger from the heater.
Installing
Install in reverse order of removal. When doing this, note the following:
- Check seals - A - and - B - on the heat exchanger for damage.
• An incorrectly glued seal can roll up into heater when sliding in the heater core.
• Cold air may flow past heat exchanger if seal is damaged or not properly fitted.
- Check the heater (while the heat exchanger is removed) through the opening - A - for the heat exchanger, for dirt.
- Remove any dirt or coolant which has leaked out of the heater (for example, after removing a leaking heat exchanger).
- Install the heat exchanger into the heater.
- Coat sealing rings - 1 - with coolant before installing.
- Install the seals - 1 - into the connection in the heat exchanger.
• Ensure sealing rings are installed on the proper side, as shown in the illustration.
• If hose clamps are deformed, replace them.
- Attach the coolant pipes to the heat exchanger.
- Hose clamps - A - must be able to be twisted slightly when installing onto the coolant pipes.
- Hose clamps - A - must be installed as illustrated.
- Tighten hose clamps - A - to 2.0 Nm.
- Make sure the clamps - A - are tight after tightening the screws. They must completely enclose the flange on the heat exchanger and coolant pipe and must not come in contact with other components.
- Thread the bolt - A - into the connection flange - B - and while doing this make sure bolt is actually threaded into the mounting point intended for it.
- Make sure the grommet - C - fits correctly inside the bulkhead.
- Seal flange for coolant pipes to heater core - A - and for expansion valve (to evaporator, only in vehicles with A/C system) - B - at pass-through of grommet - C - with silicon adhesive sealant if necessary (to prevent water from penetrating).
• Sealing rings must always be replaced.
• If hose clamps are deformed, replace them.
• After replacing heater core, coolant must be replaced completely.
• Check the coolant circuit for leaks. Pay attention to the connection between the coolant pipes and the heat exchanger.