[moldcad]

In this thread http://www.bimmerfest.com/forums/sho...d.php?t=750418 I mentioned some problems I'm having with the HVAC system in my F10, namely:

- the cold air from central vents is never really cold (even with the thumbwheel fully at the blue position)
- the air inside the car is humid
- I got the car brand new in January 2013, and in april 2013 I already started feeling the nasty smell, especially when first starting the car after several days in the garage

So I decided I just have to do something about it (BMW wants to charge me some sick money for it as they say its' not covered by warranty). I was already about to replace my microfilters (which are dirty and wettish), when I hesitated as I'm unsure whether the air pushed through it comes directly from the outside (in which case it might get wet from rain or alike), or is first cooled down and dried by the A/C in which case it should be completely dry, unless... unless my A/C developed some fault. If the latter is true, I should repair the A/C first, and replace the cabin filter only afterwards.

Please help me answer the above question (typed in bold); I looked for some diagrams but found nothing conclusive. A link to the BMW HVAC diagram would be helpful, too.

So, once again:

Does the air enter the microfilters directly from the outside, or is first cooled down and dried by the A/C?

TIA!

[HighlandPete]

Originally Posted by moldcad;*****002

- the cold air from central vents is never really cold (even with the thumbwheel fully at the blue position)
- the air inside the car is humid
- I got the car brand new in January 2013, and in april 2013 I already started feeling the nasty smell, especially when first starting the car after several days in the garage

Please help me answer the above question (typed in bold); I looked for some diagrams but found nothing conclusive. A link to the BMW HVAC diagram would be helpful, too.

So, once again:

Does the air enter the microfilters directly from the outside, or is first cooled down and dried by the A/C?

TIA!

I assume you are using the full A/C function, even in colder weather, to dry the air?

The linked document should help you understand the system. It is for the F01 7-series, we have the very similar/common system in the F10/11, even if we don't have the 4-zone option.


http://www.kneb.net/bmw/F01-02/08_F0...%20Control.pdf

HighlandPete

[moldcad]

Yes, of course i have the full A/C always on, also in winter. Thanks for the link!

[raleedy]

1. Your Bimmerfest link above seems to be broken.
2. So does your a/c. The only other possibility that occurs to me is water intrusion somewhere. Is your car garaged?

[moldcad]

Thanks - link fixed, car garaged and my BMW dealer says everything is OK (apart from the filters that require replacement - after just 17k km). May I know which part of my description makes you so positive my a/c is broken?

[raleedy]

It sounds as if you have excess moisture inside your car. Genius that I am, I suspect that this is a result of either (a) too much moisture coming in, or (b) too little moisture being removed. The latter problem would indicate an A/C fault.

[ezmaass]

I'm surprised BMW won't do anything about this? Given that the car isn't getting cold from the A/C and there's a moisture build-up, I'd suspect a problem with the A/C compressor. Air may still be blowing from the vents, but it doesn't sound like the A/C is working - if so, the air would be dry, cold, and "stink-free."

I would take it to another dealer if this one can't find a problem - A/C should be pretty basic to diagnose.

[Mbbrewer]

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