[JT - '02 330i]

I was reading through the manual, and it says that when in auto recirculation mode the climate control will normally let in fresh air, and when it detects certain pollutants it will automatically switch the climate control to cut off outside air.

Two questions:
- Just what does it detect to switch to cut off the inside air?
- Is there any visible indicator that the system is working?

Thx.

 

[·clyde·]

- Is there any visible indicator that the system is working?

The only visual indicator is the thing between your eyes, and only then if yours is big enough to see

I leave it in auto, and occasionally I'll put into manual recirc because something stinky comes in that doesn't seem to faze the auto system. It would be nice if it told you which mode it was in.

 

[The HACK]

I was reading through the manual, and it says that when in auto recirculation mode the climate control will normally let in fresh air, and when it detects certain pollutants it will automatically switch the climate control to cut off outside air.

Two questions:
- Just what does it detect to switch to cut off the inside air?
- Is there any visible indicator that the system is working?

Thx.

I don't know what it detects to switch, but if you listen VERY carefully you can hear the outside vent closing when it goes into the recirculation mode. It is a very faint noise, try sitting in your driveway in idle (don't do this in a closed garage!) and cycle your system from drawing fresh air to manual recirculation...You should hear a very very faint mechanical whirl followed by slightly increased airflow noise from the vent.

It makes that noise when it detects pollutant of certain size I think...

 

[Plaz]

I've heard it switch over a few times when behind big smoky buses or trucks... and definitely noticed the LACK of fumes I'm able to smell as a result.

Unless my windows and/or roof are open, of course.

 

[AF]

Re: Re: AUC Auto Air Recirculation - pollutants? Ever work for you?

I don't know what it detects to switch, but if you listen VERY carefully you can hear the outside vent closing when it goes into the recirculation mode. It is a very faint noise, try sitting in your driveway in idle (don't do this in a closed garage!) and cycle your system from drawing fresh air to manual recirculation...You should hear a very very faint mechanical whirl followed by slightly increased airflow noise from the vent.

It makes that noise when it detects pollutant of certain size I think...

Hey Hack . . . nice job on the sig :thumbup: