FYI: correct setting of the HVAC

[JCL]

I agree with practically all of the original post, but there is an inconsistency. If you leave the centre thumb wheel at the white line, you will get the same temperature air blowing out as is blowing out the other vents. It might be cool, but it might be warm, depending on what the HVAC system is trying to achieve at that moment.

I agree with the benefit of cooler air in my face, to stay alert. For that reason, I leave the thumb wheel on one blue dot (which means one degree cooler). If I left it on the white line, I wouldn't get the benefit of cooler air on my face. The white line setting is for those who don't want the cooler air out that one vent.

There is another subtlety that isn't addressed. My X5 had a fully automatic setting (as described in the post) but as I recall it also had a type of semi-automatic mode, in that you could let the system decide the ratio of top vent/bottom vent and you set the fan speed, or you can adjust the vent mixing and let the system choose the fan speed. In extreme climate conditions (ie -30C) the automatic mixing wouldn't keep the windshield clear. I could either prioritize the windscreen vent over the other vents, or I could boost the fan speed. The former allowed me to keep it in automatic mode as I recall.