mrahman
12-03-2007, 05:21 AM
Hello all,
I currently have a '04 745 Li and I am a little curious about my heating system. It seems like when I have it @ a cooler temperature (i.e. 60 degrees) the air comes out from all the vents, but when I start to increase the temp. (i.e. 80 degrees) the air doesn't come through the front vents. I have it set to auto / auto for both sides when the heat is running. Any reason for this? I noticed that the air is coming out full blast from the center console that has the vents pointed to the backseats.
Thanks
AwesomeIsLuke
12-03-2007, 08:07 AM
Its the auto setting. If you want it to come out the front vents just use the other settings.
Qsilver7
12-03-2007, 11:56 AM
You have the newest 7 series out so I'm not that familiar with it...but it sounds like the HVAC system still has the stratified air system set-up like BMWs have had for decades.
The stratified air system is set up to allow the driver to blow cooler air into their face to keep them alert on long journeys...so heat is usually blown to the floor and windshield vents...and the dash vents have a seperate air controller that can be set to cool or warm.
Check your owners manual about the CLIMATE CONTROL system and see if they don't mention something about this. But again, my e30/e34/e32/e38 all have/had the ability to adjust the air temp of the dash vents irrespective of the rest of the system.
Below is the Stratified Air distribution diagram (in a simple form) that basically resembles every HVAC system in all of the BMWs I've owned...again, check your owners manual to see if it has a similar set-up (I'm sure yours is infinitely more complex)...but it should be similarly adjustable. Your owners manual is the 1st step toward enlightenment: :)
http://memimage.cardomain.net/member_images/7/web/739000-739999/739005_105_full.jpg
...and the dash vents have a seperate air controller that can be set to cool or warm. Look in your climate menu for a slider that goes from red to blue. This controls the mix of hot/cool air that comes out the dash vents, which performs the same function as the manually operated dial on E38s Q referred to above.