air conditioner smell

[jd hauler]

I've heard about a filter somewhere that is replaceable, I had my ac on the other day and it had a musty smell. Anybody know how to fix?

[siume99]

Try "bco's" site

 

http://www.picturetrail.com/bco

a more direct path is:

http://www.picturetrail.com/gallery....d=62726

and just click on cabin air filter

 

And for more commentary about the topic try the thread:

http://www.gm-trucks.com/cgi-bin....+filter

 

Any "new" truck with AC has the cabin air filter (whether they are accessible is another story ).  I'm not exactly sure if its the filter's problem.  Any air that comes in from outside the truck comes through the filter.  So basically it's all the time unless you have the recirculation button on.  Try the "Outside Air" button to the left of the "Recirculation" button without the AC.

 

Hope this helps.

[carguru]

The musty smell is coming from mold and mildew growing the the HVAC plenum.  Comes from the condensation from the A/C core and/or poor drainage of the plenum.  This doesn't really have anything to do with the filter.  A couple of cures for this:

 

1. Cut off a/c a couple of miles before your destination, put the vent control on, fan control on high and heater on.  This will dry the condensation off and not allow any of the mold to grow.  Drawback is that passengers will complain about it on a hot summer day.

 

2. There is a spray that will kill the mildew in the plenum.  I believe the name of it is Pure Air or something like that.  It is a A/C ductwork cleaner.  You do this by turning the heat on high, with the fresh air intake open and douse the fresh air intake and the ducts with this spray.  Smell should be gone.  They sell this stuff near where you get the little refrigerant cans in any parts store or Wally world.

 

I've tried both.  The second method works better, but works best if the two are combined.  If you already have the problem, you have to kill the mold first.

[obyone]

Course free under warranty is better:

 

 

 

 

A/C - Odor Emission in Hot Weather

 

File In Section: 01 - HVAC

 

Bulletin No.: 99-01-39-004A

 

Date: May, 2001

 

TECHNICAL

 

Subject:

Air Conditioning Odor (Install Kit)

 

Models:

1993-2002 Passenger Cars

1993-2002 Light & Medium Duty Trucks

 

This bulletin is being revised to update the model years, service procedure, parts information and to add the GEO and Medium Duty models. Please discard Corporate Bulletin Number 99-01-39-004 (Section 01 - HVAC).

 

Condition

 

Some customers may comment on odors emitted from the air conditioning system, primarily at start-up in hot humid climates.

 

Cause

 

This odor may be the result of microbial growth on the evaporator core. When the blower motor fan is turned on, the microbial growth may release an unpleasant, musty odor into the passenger compartment. There are several other possible sources of a musty odor in a vehicle. A common source is a water leak. Follow the Service Manual procedure for identifying and correcting water leaks if other odor sources are found. The procedure contained in this bulletin is only applicable if the source of the odor has already been determined to be the HVAC module.

 

Correction

 

To remove odors of this type, it is necessary to eliminate the microbial growth and prevent its reoccurrence. To accomplish this, the following steps must be completed:

 

1. Apply evaporator core Cooling Coil Coating

(Aerosol 6 oz), P/N 12377951 (AC Delco® 15-102)

(in Canada, use P/N 10953503) or Cooling Coil

Coating Kit with Extension Nozzle, P/N 12346391

(AC Delco® 10-120).

 

Refills are available for the Cooling Coil Coating

Kit with Extension Nozzle, P/N 12346391

(AC Delco® 10-120). Refer to the chart below.

 

2. Install the Electronic Evaporator Dryer, P/N 12497910 (AC Delco® 15-5876).

 

Important : The Cooling Coil Coatings listed above are the only GM approved products for the disinfection and long-term control of evaporator microbial growth. The Cooling Coil Coating will disinfect the evaporator core and help inhibit the growth of future mold and mildew.

 

The Electronic Evaporator Dryer will activate when the ambient temperature near the module is above 16°C (60°F) when the vehicle is started up. Approximately 30 minutes after the vehicle has been turned off, the blower will activate for 10 seconds every 10 minutes for 2 hours unless the vehicle is restarted. If a restart occurs, the Electronic Evaporator Dryer module will reset automatically. This on/off blower activation will dry the evaporator core and case reducing the chance of reoccurring A/C odor. The Electronic Evaporator Dryer is self fused and has a battery rundown protection feature that inactivates the dryer if voltage drops below 12.5 volts.

 

Service Procedure

 

1. Visually inspect the air conditioning evaporator drain hose for obstructions and/or working condition.

 

2. The cooling coil coating fluid must be applied to a dry evaporator core. Apply coil coating fluid as described in the instructions supplied with the kit. In some instances, the blower motor resistor can be removed for this spraying operation. If used, the opening can be taped over and the nozzle inserted through a hole in the tape. The kit instructions identify a drilling procedure to apply the coating fluid. When using this type of procedure, care must be taken to avoid evaporator damage and any holes must be properly sealed. Some coating fluid may overflow from the drain hose.

 

Important : When installing the Electric Evaporator Module, you MUST use the included electrical splice connectors to ensure a splice.

 

3. Complete detailed installation instructions and wire connectors are supplied with the Electronic Evaporator Dryer. The ground wire should be attached to a body ground source. If any other wire splicing procedures are needed, follow the wire repair procedures in the Electrical sub-section of Body & Accessories in the appropriate Service Manual. If required, the evaporator dryer can be installed underhood away from extreme heat conditions (i.e. exhaust manifolds) and/or water splash areas. In all cases, the evaporator dryer module must be secured with a Velcro® strip (not included in the kit), or you may use the integral hooks to utilize tie straps. Using a Velcro® strip is preferred as the use of the integral hooks may cause rattles.

 

4. When the installation procedure is complete and power is supplied, the module will self-test. Thirty seconds after power is supplied, the high blower speed will be activated 3 times (for 2 seconds per cycle). When the test has run, install the Electronic Evaporator Dryer label on the blower motor case in a visible area.

 

Parts Information

 

Parts are expected to be available from GMSPO, 6/4/01.

 

Warranty Information

 

For vehicles repaired under warranty, use the table.