Even as far back as early E32's some BMWs have had particulate matter
sensors that changed the airflow to recirc until either the incoming air was
clean again or a certain number of minutes (8? 20? can't remember quite)
had elapsed and the cabin air was going to be getting stale with CO2 from
Bmw's like most high priced cars have an sensor mounted in the air
intkae of your heating system that sniffs the air temp and air quality
and adjust your recurculating flap to open of closed for economy and
quality reasons thats a good thing
Dave Plowman (News) wrote:
In Auto, it is supposed to go to Recirc by itself if it smells foul air. You
can set the system to Auto, and then manually set Recirc to ON so the system
Recircs all of the time. You may want to do this when it's raining or foggy
because Recirc air will be dryer than outside air, and this will help the
glass to clear.
If the AC is on, Recirc should provide drier air than pulling from the
outside. If the AC is off, then the moisture in the air will simply build
and build if Recirs is on, then the windows will fog even worse. Setting the
Air Conditioner on is key. Some cars, not BMW, automatically set the AC on
and Recirc the air when Defrost is selected. I prefer the way BMW allows us
to set the life support systems however we want, but all automakers are not
...so, it somehow knows a bad smell and keeps it from entering the cabin? If the answer is yes, how does it know???
face="Lucida Sans Unicode">...<BR>>> My 2001 330ci has an air circulation
option. One is supposedly used when <BR>>> the AC system is set to auto.
The other is for "non" auto. I can't think <BR>>> of a single reason to
have this switch. When re-circulation the air in the <BR>>> cabin, what
difference does it make if the system is set to auto or <BR>>>
non-auto? TIA<BR>>> <BR>> <BR>></FONT></BODY></HTML>
Two things, turn off the HTML (Rich Text), and I don't know how it knows
that you are driving past a pasture or behind a bus. Certainly this is not
rocket science though, and is a relatively simple thing to ascertain. Clean
air has a certain electrical property, and if that property changes it is
safe to assume that the air isn't so fresh anymore.
On Fri, 29 Jul 2005 15:01:28 -0700, "Jeff Strickland"
Probably a bit like how your nose can recognize the smell of a fart in
100 milliseconds or so. The problem is making an electrical
sensor/circuit that will do it. Evidently, the motor makers already
did that. Now they need to develop the technology that will clearly
identify the offender, open the door and push him/her out of the car.
Think you've misunderstood the meaning. Auto recirc has no link to auto on
the climate control - it simply defaults to fresh air, but changes to
recirc if it detects noisome air. It explains this in the driver's
*Stable Relationships Are For Horses. *
Dave Plowman email@example.com London SW
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