A/C - Musty Odors From Heater and A/C Systems
SI 64 04 03Heating and Air Conditioning
October 2004 Technical Service
This Service Information bulletin supersedes S.I. 64 04 03 dated December 2003.
[NEW] designates changes to this revision
SUBJECT
Air Conditioning System Musty Odor
MODEL
ALL
SITUATION
The customer may complain of a musty odor that is coming from the heating and air conditioning system.
CAUSE
Certain environmental conditions may cause a musty odor when the air conditioning system is used.
PROCEDURE
Clean the heating and air conditioning system using the Wynn's Aircomatic Cleaning tool. Refer to SI B04 30 03 on information on how to acquire the tool and the cleaning solutions.
The following items are needed to complete the cleaning procedure:
1. Wynn's Aircomatic Ultrasonic Cleaner (P/N 211-0300).
2. Wynn's Airco clean (P/N 211-30208).
Some of the advantages of this new tool are as follows:
^ No drilling or disassembly of the vehicle is necessary.
^ Ease of use; tool can be started and then left unattended to finish the cleaning.
^ The cleaning procedure is very effective for not only cleaning the evaporator but can rid the interior of the vehicle of certain odors.
Before the cleaning procedure is carried out the following points should be taken into consideration;
^ Always inspect the microfilters and replace as necessary.
^ Inspect the microfilter housing water drains for clogging and clean as necessary.
^ Some vehicles (E38 7 Series) have recirculating air filters that need to be inspected and replaced as necessary.
^ Make sure the evaporator housing drains are not clogged.
^ Always verify customer complaint, sometimes the vehicle interior carpet may be soaked because of a water leak. Also inspect the trunk for water leaks or items that may cause a smell.
Safety Precautions
Always wear proper eye protection. The use of safety goggles or glasses, gloves and shop coat is recommended.
Always set the vehicle's parking brake before any work is performed.
Before starting the engine, check to be sure that the vehicle's fan blades, pulleys, belts and other moving parts are clear of any obstructions.
[NEW] AIRCO-CLEAN A/C Treatment Application
1. Start the vehicle's engine.
2. Turn the air conditioning off.
3. Set the blower to a middle speed.
4. Open all dashboard center air vents and set the airflow control to direct air toward the dashboard center vents and not through floor facing vents or window defroster vents.
5. Set the ventilation system to recirculate.
6. Ensure that there is no remaining liquid from a previous treatment in the unit.
7. Shake the bottle of Wynn's AIRCO-CLEAN Ultrasonic Air Conditioning Treatment.
8. Remove the cap from the bottle.
9. Turn the bottle of AIRCO-CLEAN Ultrasonic Air Conditioning Treatment upside down and screw the bottle (hand-tight) onto the filling opening of the unit. The spike in the AIRCOMATIC unit will puncture the bottle seal and allow the liquid to empty into the unit. Leave the bottle attached for the duration of the service.
10. Connect the clear flexible hose to the spout opening on the AIRCOMATIC unit.
11. Place the AIRCOMATIC unit in the passenger side footwell.
12. Make sure the machine is placed horizontally and not at an angle.
13. NOTE: As the AIRCOMATIC unit creates 5-micron droplets; it is not necessary to remove the vehicle's pollen filter (this generally filters fresh air and not recirculating air). The product will pass through the pollen filters. However, activated carbon/charcoal filters should be removed during the treatment and replaced if necessary at the completion of the service, as these filters will absorb the AIRCO-CLEAN product.
14. Point the clear flexible hose away from the face and skin. Attach the power cord from the transformer into an 110V wall outlet and the opposite plug into the AIRCOMATIC electrical socket. The unit will immediately begin producing vapor through the flexible hose. Make sure the hose is not kinked. Direct the hose so that the vapor is pulled into the ventilation ducts above the passenger side footwell. This will direct the vapor into the air conditioning system evaporator and back into the vehicle's interior through the open dashboard vents.
15. Close all doors and let the treatment continue.
16. It is important to stop the treatment after 15 minutes. If the unit is run any longer it may overheat and may shorten the lifespan of the unit.
NOTE:
Some condensation will occur in the clear plastic hose. Exercise caution when removing the unit to avoid spillage.
17. Disconnect the power supply.
18. Remove the flexible hose from the AIRCOMATIC unit.
19. Remove the empty bottle of AIRCO-CLEAN product.
20. Turn the unit upside down and pour any remaining liquid through the flexible hose connection opening into the empty bottle. This liquid will typically be discolored due to the heat produced in the unit.
21. Do not rinse the unit. Emptying the machine of remaining fluid is sufficient.
22. The AIRCOMATIC unit is now ready for the next service.
23. Open the vehicle's windows set the A/C control to the ON position (normal operation), the temperature to the coldest setting and the blower to the highest setting. Allow the vehicle to air-out for at least 10 minutes prior to driving the vehicle or releasing it back to the customer.
In some extreme cases the evaporator may still need to be flushed out. For this procedure refer to SI B64 08 91.