A/C - Unpleasant Musty Odors
Group: 87Number: 05-01
Date: Jan. 7, 2005
Subject:
Musty Odor from Heating and Ventilation System
Model(s):
See Table
Condition
Unpleasant "musty" odor from Heating and Ventilation system.
Odor mainly occurs after vehicle has been sitting (unused) at least 5 hours and within 20 to 60 seconds after vehicle is first started.
This odor may be caused by residual condensate in and around evaporator mixing with airborne pollutants. This forms the growth of bacteria and or fungi (mold).
Tip:
Condensate is a normal condition in all A/C Systems.
Tip:
If odor is noticeable without engine started, this may be due to mold and mildew in the passenger compartment, not from the A/C system.
Applicable Models and Years
Vehicle Requirements
^ Fresh air plenum drain(s) must be open and free of any debris. See appropriate Repair Manual for location.
^ Bulkhead must be sealed (no leaks/water ingress into passenger compartment).
^ Evaporator housing drain valve must open. See appropriate Repair Manual for location.
Required tools
- AIR62637 applicator tool
Air compressor
1 (4 fl. oz.) bottle of Airsept(R) Air Conditioning treatment
WARNING
Keep product out of the reach of children. Wear skin and eye protection (prevent contact with skin or eyes.
If product comes in contact with skin or eyes, rinse thoroughly with clean water DO NOT inhale vapors (stay away from open vehicle windows until product has dried).
If Possible, application should be conducted in an open environment, or at least with adequate circulation and ventilation.
WARNING
ALWAYS read and follow accompanying Airsept(R) product Safety Precaution!
Tip:
^ Actual working time is approx. 30 minutes. Complete procedure takes approx. 2 hours including drying/hardening time.
^ Follow procedure precisely If specified drying/hardening time is not complied with, the product will be washed off by condensation and treatment will not work.
^ If applied properly Airsept(R) will inhibit the new growth of bacteria and mold for approximately 1 year
Service
Vehicle preparation
This portion of the service procedure will remove condensation from the evaporator core.
- Remove right side plenum cover, clean any accumulation of debris (leaves, twigs etc.).
- Remove air intake adapter, pollen filter (if equipped) exposing passenger compartment air intake -arrow-.
Note:
Take care not to damage seal when removing air intake adapter.
- Inspect pollen filter case seal for damage. Replace if necessary.
- Place a catch basin below evaporator housing drain valve.
- Open and center all A/C outlet ducts.
- Cover all front and rear A/C outlet ducts with paper towel -arrows-.
Tip:
Do not cover A/C outlet ducts with any material that would prevent air from exhausting from ducts.
- Record customer's climate control settings.
Tip:
Illustrations are used for reference to procedure only actual A/C control views may differ from what is shown.
- Remove A/C clutch fuse from instrument panel fuse box, if applicable. See owners manual for appropriate fuse.
- Set Control as follows:
- Econ mode ON.
- Temperature to warmest setting.
- Blower to highest speed.
- Air distribution to A/C ducts.
- Driver side window open.
^ All other windows and sunroof closed.
- Start engine and run engine for approx. 20 minutes.
WARNING
Never start or let the engine run in a confined or enclosed unventilated area. Exhaust fumes from the engine contain carbon monoxide, which is a colorless and odorless gas Carbon monoxide can be fatal if inhaled.
- Never leave vehicle unattended while engine is running. An unattended vehicle with a running engine is potentially hazardous.
^ After 20 minutes: system should be dry (free of any moisture).
Tip:
If system is not fully dried, Airsept(R) will wash away with newly formed condensate.
Airsept(R) Application
Engine should be running at idle and HVAC controls unchanged.
- Thoroughly shake bottle of Airsept(R) and install onto AIR62637 applicator tool.
- Connect AIR62637 applicator tool to shop air.
Tip:
^ Air supply must be non-oiled shop air.
^ Air supply line pressure to tool must be 60-85 psi. or greater to provide the desired coverage.
- Insert AIR62637 applicator tool in air intake in plenum with nozzle pointed towards evaporator as shown.
Note:
DO NOT contact blower motor cage with applicator tool as damage to tool and/or cage may occur.
- Position applicator tool nozzle just above blower motor cage -arrow-.
- Apply short bursts (approx. 3-5 second) of Airsept(R) treatment.
^ Continue treatment (3-5 second bursts) until bottle is empty.
Airsept(R) Treatment, Drying
- Run engine for approx. 20 minutes (HVAC controls unchanged).
- Switch ignition OFF.
- Remove paper towels from A/C ducts.
- Install A/C clutch fuse in instrument panel fuse box, if applicable.
- Connect VAS 5051/5052 diagnostic tool.
- Interrogate and erase any DTC(s) in Address word "08 - Air conditioning/heating electronics".
- Return climate controls to customer's settings.
- Let vehicle sit for a minimum of 1 hour with windows open (preferably with doors open if possible).
- Enter date of Airsept(R) treatment into the vehicle maintenance record.
After Airsept(R) treatment
Explain to the customer that running the air conditioner during Spring and Fall months reduces the chance for airborne pollutants to adhere to the evaporator and housing.
Airsept(R) tool, cleaning
- Remove Airsept(R) bottle from tool, remove tool from vehicle, flush tool and bottle with clean water.
- Add 2 ounces of clean warm water to Airsept(R) bottle and reinstall onto AIR62637 tool (DO NOT reinstall tool on vehicle), then apply air pressure until bottle is empty, flush tool with clean water and discard Airsept(R) bottle.
- Reinstall seal, air intake adapter, pollen filter (if equipped) and right side plenum cover.
When procedure applies to vehicles within the New Vehicle Limited Warranty, use the table.