UUronL

As noted here many times, to keep the AC from smelling you're supposed to turn the compressor off 10+ minutes before you arrive somewhere so that the system can purge the condensation that has been built up. If not, it mildews and gets musty/smelly.

Anyway, I had an idea today - the heat here has been unbearable, and it isn't practical to shut the AC off at any point when in the car. My idea was once I park the car and just before turning the engine off, I set the timer for the auto-ventilation system for the minute right after the time showing on the clock. Guess what? It works - the blower comes on and the condensation is blown out the vents.

Make sure to angle the vents away from the steering wheel - it gets wet if you don't.



That got me thinking though - it would be trivial for BMW to code the climate systems to keep the blower on after the car is turned off to purge the AC. They could even add a moisture sensor on future models to determine when to turn it on and off. But even now with our cars, it should be easy... if the AC was set to "on" when the car was shut off, run the blower for say 10 minutes.

Rudy

You don't have to set the timer, you can simply activate the "parked car ventilation" feature before leaving the car. Just make sure the key is in position 1 -- otherwise the option is greyed out...

UUronL

Yeah, I know - I just forgot the position 1 bit... couldn't get it to work today, but I know that check box is the way to just switch it on manually.


My point remains though - if you read the manual (which I just re-read) it only mentions its use to lower the cabin temperature. I feel that the same function can be used to permit the blower to purge the condensation from the AC after you shut the car off and get out. For that, I doubt the 30 minute period is necessary. If BMW wanted to, they could make a 10 or 15 minute option labeled "Parked AC purge" or something.

Rudy

I understand your point and agree that using the system to blow air with the car off may be a good idea (which is why I added the information on how to accomplish it with less hassle.)

One thing I can't figure out though is why this odor problem has never been an issue for me. I always keep my a/c and my air recirculation setting on automatic (and have done so on my last four 5ers) and I simply don't ever have any foul odor. Sure, you may be in a climate that's slightly more hot or more humid but not by much. We've had our share of the heat wave these past few weeks as well and over the years and I've clearly operated my car in some serious heat during that time. Why don't I get this mold buildup? (I never run the fan without the compressor before shutting the car off...)

Member545

It has happened to me, it is very annoying. I really hope they do something about it. I mention it everytime I bring the car in for service.

EBMCS03

Hummmmm good idea... now that I've eliminated 85% of my AC smell I need to start doing this. It was a PAIN in the REAR to get rid of the AC smell..

UUronL

Dunno Rudy. I grew up in Pgh (my car and I will actually be there this weekend) - but DC (where I live now) is far worse. My previous two cars were German, and they both had a smell issue. I have been hyper-careful with the BMW, and so far no issues - however I blow the condensation out every time. I run the blower until I smell what I can only describe as vinegar-like odor. Once this passes and the air smells like nothing, I know I'm in the clear.

Lord Monkey

Does the car not leak condensation out onto the road from below? I know someone at work who called out roadside recovery because he thought his radiator was leaking, only to be told the water coming from under the car was his a/c draining condensation!

UUronL

I believe that is condensation that forms on the external surfaces of the compressor, etc... I doubt it's coming from inside. Kind of like the water that forms on the outside of a cold drink, etc...

The problematic stuff is the same, but forming in all the nooks and crannies of the vent and duct system. Anytime something that was very cold starts getting warmer, this happens. Same reason a camera will fog up if you take it from a nice air conditioned house into the heat outside on a hot day.

BMWSTL

I have never had this issue in any car I've ever owned. I live in St. Louis which is hot with high humidity all summer. I don't do anything with the A/C beyond just shutting off the car.

Maybe it's the driver.

Lou