Evaporator, A/C Unit Installed
Evaporator, A/C Unit Installed
Special tools, testers and auxiliary items required
• Pliers (T40147)
• Strong carpet knife with a point; the blade must be secure and the handle must be strong.
• The removed evaporator contains refrigerant oil that must be returned to the refrigerant circuit (with the new evaporator).
• Revised A/C units and evaporators are being installed from MY 12 (use depends on the vehicle version) (A/C unit part number "8T_ 820 005"). It is not possible to replace the evaporator on this A/C unit when the A/C unit is installed. See if the evaporator is available as an installation kit either without the evaporator housing or only together with the housing. Refer to the Parts Catalog. If the evaporator is available only together with the housing, then it is necessary to remove the A/C unit and replace the evaporator with the evaporator housing. Refer to => [ Evaporator Housing ] Evaporator Housing.
• Evaporators with a block depth - A - of approximately 40 mm (1.6 in) (air conditioner part number "8K_ 820 005") are being installed from start of production through the change-over from MY 12. These evaporators can be replaced with the air conditioner still installed. From MY 12, Evaporators with a block depth - A - of approximately 50 mm (2 in.) are being installed (air conditioner part number "8T_ 820 005") as a running change depending on the vehicle version. These evaporators can be replaced only with the air conditioner removed together with the evaporator housing. Refer to the Parts Catalog.
• There is a label - A - on the outside of the A/C unit with a part - B - that tells which version is installed. Refer to Electronic Parts Catalog (ETKA).
• The part number - B - on the decal - A - can be read when the CD changer is removed (depending on the vehicle equipment level). Refer to Electronic Parts Catalog (ETKA).
• Pay attention to the correct allocation of the evaporator expansion valve (there are different versions). Refer to Electronic Parts Catalog (ETKA).
• The refrigerant pipe - D - on the Audi Q5 hybrid is wrapped with insulation (butyl or tar tape) to reduce noise. The insulating tape shields the A/C compressor noise, which seems to be louder when the engine is idling.
• If the evaporator is going to be replaced on an Audi Q5 Hybrid, then wrap the refrigerant pipe - C - on the replacement evaporator with insulating tape. Approximately 30 cm (12 in.) of 5 cm (2 in.) wide insulating tape (commercially available butyl or tar tape) - B - with a 3 mm strength will be needed.
• This insulating tape - B - is used when handling refrigerant as commercially available butyl or tar tape. It is available in refrigerant materials stores and comes in rolls approximately 10 m (33 ft.) long.
Removing
- Move the driver and passenger seats as far back as possible.
- Turn off the ignition.
- Drain the refrigerant circuit.
• Depending on the allocation of the service connection an on the refrigerant line, and on the version of the vehicle, it may be necessary to remove the additional reinforcement on the left suspension strut dome so that the service coupling of the service station can be connected (for example, on the Audi Q5).
• It may be necessary to remove the cowl panel - C - in order to remove and install the expansion valve.
For vehicles without a high voltage system
- Turn off the ignition.
- Remove the plenum chamber cover and/or the cowl panel (there are different versions).
- Disconnect the ground cable from the battery (A).
• Disconnect the battery (A) ground connection so that it cannot short circuit when the jumper cable post - C - is removed.
- Remove the jumper cable post cover - C -.
All vehicles
- If equipped and necessary, remove the suspension strut dome - B - (for example Audi A5 Coupe, not necessary for example on the Audi Q5).
• The plenum chamber front wall cannot be loosened or removed from the vehicle (there is not enough space available).
• Both coolant hoses are routed to the heater core through the plenum chamber front wall - A -. On these vehicles, loosen the grommet on both coolant hoses and move the plenum chamber front wall to the side (when doing this, the refrigerant circuit must not be opened).
• When loosening the plenum chamber front wall, be careful not to damage the brake booster vacuum line.
- Remove the expansion valve. Refer to => [ Expansion Valve ] Expansion Valve.
• Seal open pipe connections.
- Remove the expansion valve mounting plate - A - from the refrigerant lines - B - and - C -.
- Remove the storage compartment on driver's side.
- Remove the left footwell (driver side). Refer to => [ Left Footwell Vents ] Left Footwell Vents.
- Remove the steering column.
- Remove the pedal assembly and accelerator pedal module.
- Remove the screw - A -.
- Loosen the locking mechanism - C - and remove the cover for the refrigerant lines leading to the evaporator - B -.
- Disconnect both refrigerant lines leading to the evaporator - A - and - B - at the location identified with - E - using (T40147).
• This illustration show the refrigerant pipes - C - and - D - to the evaporator not wrapped with butyl or tar tape.
• The refrigerant pipe - D - on the Audi Q5 hybrid is wrapped with insulation (butyl or tar tape) to reduce noise. The butyl or tar tape shields the A/C compressor noise, which seems to be louder when the engine is idling.
- Loosen the disconnected refrigerant lines - C - and - D - from the grommet - F - and remove both refrigerant lines.
- Bend the part of the refrigerant line - A - (which is already on the evaporator) to the right (to the evaporator) so that it does not interfere when removing the evaporator.
- Remove the glove compartment.
- Remove the air intake housing. Refer to => [ A/C Unit Air Intake Housing ] A/C Unit Air Intake Housing.
- Cut the housing wall - A - (on the right side of the A/C unit) using a sharp knife (for example, a strong carpet knife with a point; the blade must be secure and the handle must be strong.) along the marked cutting line from the A/C unit.
- Remove the evaporator - B - in the direction of the arrow - arrow - from the A/C unit.
Installing
Installation is carried out in the reverse order while observing the following.
- Check the A/C unit via the evaporator installation shaft for dirt; clean the A/C unit if necessary.
• When doing this, pay attention to both condensation water drains - A - and their openings - B -.
- Check both connections - B - and - C - on the replacement evaporator - A - for dirt and damage.
- Install both covers - D - and - F - on the correct side on the evaporator.
• Both covers are included in the replacement evaporator kit. Refer to Electronic Parts Catalog (ETKA).
• Depending on the cover version - D - cut the part - E - from this cover (on the side with the connections installed).
- Push the evaporator - A - into the A/C shaft; when doing this, be careful not to loosen the covers - D - and - F - from the evaporator.
- Install the bracket - A - with the bolt - B - on the evaporator connector.
- Check the refrigerant lines - C - and - D - for damage and dirt.
• Even slight damage (a scratch) or a little bit of dirt (a hair) can cause leakage at a connection.
• The refrigerant lines - C - and - D -, the O-rings - E - and - F -, the bracket - A - and the bolt - B - and - H - are all included in the replacement evaporator kit. Refer to Electronic Parts Catalog (ETKA).
- Install the refrigerant lines - C - and - D - into the grommet - G -.
• If replacing the evaporator on an Audi Q5 Hybrid, then wrap the refrigerant pipe - C - on the replacement evaporator with insulating tape as illustrated before installing. Approximately 30 cm (12 in.) of 5 cm (2 in.) wide insulating tape (butyl or tar tape) - B - with a 3 mm strength will be needed.
• Wrap both ends of the refrigerant pipe - C - when it is removed, as illustrated. Do not wrap approximately 15 mm (0.6 in.) in area - A -. This is where a grommet will be installed facing the expansion valve. Likewise, do not wrap the connection area to the evaporator.
- Coat the O-rings - E - and - F - with refrigerant oil before installing. Refer to => [ Refrigerant Circuit O-rings ] Refrigerant Circuit O-Rings.
- Mount the O-rings - E - and - F - on the refrigerant lines - C - and - D -.
- Install the refrigerant lines - C - and - D - in the connection on the evaporator.
- Install the bolt - H -.
- Install both bolts - B - and - H - equally far enough so that both refrigerant lines - C - and - D - can be turned without pretension.
• When installing the bolts - B - and - H - be careful not to twist the bracket - A - together with the refrigerant lines.
• If the refrigerant pipe wrapping - B - touches the separating walls of the evaporator housing - C - on an Audi Q5 hybrid, rework the walls, if necessary.
- Connect the expansion valve mounting plate - A - to the refrigerant lines - B - and - C -.
- To align both refrigerant lines, first install the expansion valve, refer to => [ Expansion Valve ] Expansion Valve and the refrigerant line with the inner heat exchanger, refer to => [ Refrigerant Circuit Components ] Refrigerant Circuit Components.
• The expansion valve and the refrigerant line with the inner heat exchanger are installed first to align both refrigerant lines leading to the evaporator, and after tightening both bolts on the evaporator connect, they are removed again.
- Tighten the bolts - B - and - H - on the evaporator connector (tightening specification 5 Nm).
• This illustration show the refrigerant pipes - C - and - D - to the evaporator not wrapped with butyl or tar tape.
• On the Audi Q5 hybrid, wrap the refrigerant pipe to the evaporator with a piece of butyl or tar tape in area - A - as illustrated after tightening the screws to reduce noise. Then wrap the entire area - D - on the evaporate with another piece of butyl or tar tape.
- Remove the refrigerant line with the inner heat exchanger and the expansion valve again.
- Install the expansion valve. Refer to => [ Expansion Valve ] Expansion Valve.
- Install the refrigerant line with inner heat exchanger. Refer to => [ Refrigerant Circuit Components ] Refrigerant Circuit Components.
- Install the cover for the evaporator refrigerant lines - B - and the bolt - A -.
- Make sure the cover - B - fits correctly and that it is free of tension.
• Even the smallest lead at the groove/spring connection between the cover - B - and the air conditioner - A - will cause whistling noises. Coat the connecting surfaces lightly with silicone grease (part number G 000 405 A2). Refer to Electronic Parts Catalog (ETKA).
- Clean and dry the groove in the A/C unit - E - before installing the separating wall - C -.
- Fill the groove on the A/C unit - E - before installing the separating wall - C - for example with silicone adhesive (D 176 001 A3). Refer to Electronic Parts Catalog (ETKA).
- Install the separating wall - C -.
• The separating wall - C - is included in the replacement evaporator kit. Refer to Electronic Parts Catalog (ETKA).
• There are different versions of the separating wall - C - (with and without the spayed on sealing lip). Refer to Electronic Parts Catalog (ETKA).
• If the connecting location between the A/C unit - E - and the separating wall - C - is not sealing in area - D - condensation water from the A/C could leak into the footwell when, for example, driving around a curve.
- Remove any excess adhesive (the adhesive may only in the area - D -); and remove any excess adhesive out of the groove - G -.
- Install the air intake housing. Refer to => [ A/C Unit Air Intake Housing ] A/C Unit Air Intake Housing.
All vehicles
- Evacuate the refrigerant circuit and fill it.
- Install the remaining removed components.
- Switch on the ignition.
- Perform a basic setting and the output Diagnostic Test Mode (DTM) on the A/C system using the Vehicle diagnostic tester in "Guided Fault Finding".
• On this vehicle, the control motors are equipped with electronics. During the first basic setting, a new control motor learns its position on the air conditioner and can then be controlled by the Climatronic Control Module (J255) (currently all control motors are identical). Refer to the Vehicle diagnostic tester in "Guided Fault Finding".
• During the basic setting, the control motors are assigned and adapted corresponding to the switching sequence of the wiring. If this sequence does not conform the specification, the control motors will adapt incorrectly and the door control will be wrong. Refer to => [ A/C Control Motor Block Diagram ] A/C Control Motor Block Diagram.
- Check the Climatronic Control Module DTC memory and erase any displayed malfunction if necessary using the Vehicle diagnostic tester in "Guided Fault Finding".
- Operate the A/C system after filling the refrigerant circuit. Refer to => [ A/C System, Operating after Filling Refrigerant Circuit ] A/C System, Operating after Filling Refrigerant Circuit.
• Note the information regarding operating the A/C system after filling.