Musty odour from heating and air conditioning system, evaporator cleaning 25 February 2020
General Information
0 Comment

All model series

Complaint:

When operating the heating and air conditioning system, a musty odour briefly occurs in the vehicle. This occurs mostly immediately after starting the engine with the air conditioning switched on or after switching off the air conditioning while driving.

Cause:

The cause for the customer complaint is not a fault in the air conditioning of the vehicle. The formation of odour is due to environmental factor during the operating period of the heating and air conditioning system.

The constant condensation of air humidity at the evaporator over a long operating period of the heating and air conditioning system creates a favourable environment for bacteria and other micro-organisms.

Together with dirt contamination brought in by the fresh air, this may cause microbiological growth on the evaporator and consequently a musty odour.

Regularly changing the microfilter may reduce the entry of dirt contamination and therefore delay or prevent the development of aforementioned customer complaint.

Replacement of the evaporator has no continuous effect as microbiological organisms may redevelop.

Invoicing as warranty is not justifiable as there is no technical fault.

Vehicles concerned:

All series with air conditioning (IHKR) or automatic air conditioning (IHKA).

Procedure:

1. Evaporator cleaning with spray lance

The most efficient and lasting method of eliminating the musty odour from the air conditioning is to clean the evaporator with the aid of a spray lance. With this procedure, the disinfectant is sprayed with high pressure directly on the evaporator.

Description of the operations:

For the detailed description of the procedure for the following series, please see the respective repair instructions:

2. Cleaning with the evaporator cleaning device “Aircomatic”

As an alternative, the evaporator can be cleaned using the “Aircomatic” cleaning system made by WYNN’S. For this purpose, use the “Airco-Clean” cleaning agent made by the same company.

WYNN’S describes this procedure as “Ultrasound procedure”.

The cleaning power using the “ultrasound procedure” is lower as compared to cleaning with a spray lance.

If the “ultrasound procedure” does not bring long-term success due to very severe dirt contamination of the evaporator, clean the evaporator using a spray lance and the heating and air conditioning system cleaning agent.Note:

This procedure is to be used for vehicles for which no spray lance is offered.

Description of the operations:

  • Remove microfilter (replace with new filter after cleaning)
  • Start the vehicle
  • Switch on air conditioning
  • Set temperature control to lowest value
  • For automatic air conditioning (IHKA): Switch off automatic air distribution/supply
  • Select the lowest fan speed
  • Set ventilation to upper body area
  • Adjust air supply to air recirculation function
  • Shake the “Airco-Clean” bottle well
  • Place the ultrasound device upside down
  • Screw in the “Airco-Clean” bottle with its opening facing upwards into the device
  • Return ultrasound device to initial position allowing the contents of the bottle to partially flow into the device
  • Place the ultrasound device in the footwell on the passenger’s side
  • Connect the atomisation hose to the device
  • Place the atomisation hose so that the recirculated air system can take in the emitted vapour wellDo not kink the hose!
  • Connect the ultrasound device using the included cableAtomisation starts!
  • Close vehicle doors and side windows Attention:No one must remain in the vehicle during treatment! 
  • Treatment is complete after approx. 20 minutes and the ultrasound device stops
  • After treatment, open doors and air the vehicle for approx. 5 minutes
  • After treatment pour out the residual liquid in the ultrasound device
  • Briefly rinse the ultrasound device with water 

Parts required:

1. Cleaning with spray lance

Spray lanceOrder/part numberQuantity
-E39/E46/E53/E8364 1 4501
– E65/E66/E67 (left-hand drive vehicle)64 1 2801
– E65/E66/E67 (right-hand drive vehicle)64 1 2901
-E60/E61/E63/E6464 1 4801
– E85/E86 (left-hand drive vehicle)64 1 4901
– E85/E86 (right-hand drive vehicle)64 1 2501
– E81/E82/E87/E88/E90/E91/E92/E93 (left-hand drive vehicle)64 1 2601
– E81/E82/E87/E88/E90/E91/E92/E93 (right-hand drive vehicle)64 1 2701
– E70/E71/E72 (left- and right-hand drive vehicle)64 1 3001
– F01/F02/F03/F04/F06/F07/F10/F11/F12/F13/F18 (left-hand drive vehicle) G01/G02/G08/G29 (left-hand drive vehicle)83 30 2 222 5021
– F01/F02/F03/F04/F06/F07/F10/F11/F12/F13/F18 (right-hand drive vehicle) G01/G02/G08/G29 (right-hand drive vehicle)83 30 2 364 7331
-F20/F21/F22/F23/F30/F31/F32/F33/F34/F35/F36/F80/F82/F83/F87(left hand drive vehicle)83 30 2 344 0011
-F20/F21/F22/F23/F30/F31/F32/F33/F34/F35/F36/F80/F82/F83/F87 (right-hand drive vehicle)83 30 2 289 6131
-I0183 30 2 413 6531
-F45/F46/F48/F4983 30 2 413 6531
-F54/F55/F56/F57/F6083 30 2 413 6531
-G05/G06/G07/G11/G12/G30/G31/G32/G38/F90 (left-hand drive vehicle)83 30 2 411 7571
-G05/G06/G07/G11/G12/G30/G31/G32/G38/F90 (right-hand drive vehicle)83 30 2 414 9991
Spray gun  
SATA spray pistol81 45 9 429 2171
Heating and air conditioning system cleaning agent  
Heating and air conditioning system cleaning agent (only for cleaning with spray lance!)83 19 2 180 5071

Heating and air conditioning system cleaning agent is used undiluted. No rinsing required.

The spray lance spray gun can be obtained from the special tools online catalogue; the heating and air conditioning system cleaning agent can be obtained directly from BMW Group Parts.

2. Cleaning with the evaporator cleaning device “Aircomatic”

(Valid for all series)

DescriptionPart numberQuantity
Heating and air conditioning system cleaning agent83 19 2 409 6111

Heating and air conditioning system cleaning agent is used undiluted.

The “Aircomatic” cleaning device and the “Airco-Clean” cleaning agent can be obtained directly from BMW Group Parts.