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NoQuarter
05-11-2010, 02:42 PM
I'm trying to give the auto temp control a chance to win me over but I don't understand the heat distribution. The controls in iDrive I get, the interface is understandable - my problem is the warm and cold air distribution.

I set the temp to about 68 in the cabin. When the cabin needs to be cooled I feel the cold air from the dash as I would expect - but I get heat from the windshield defrost and heat in the foot well. This is on a sunny day with the sun heating me up and then I have to put up with heat hitting me from the defrost and feet! Is this what others experience?

A related question... there is a small fan on the dash between the front and rear defrost buttons. Is that sucking in air to measure cabin temoerature or is it humidity? I had the dash apart recently installing an iPod dock in the ash tray and I saw a temp probe in the driver side vent measuring air coming out of the vent.



Jim

AzNMpower32
05-11-2010, 04:00 PM
If you turn on the defrost, it will blow hot air by default. That's just the way it's designed to do: melt snow and ice.

The temperature sensor is located as you described between the front and rear defrost buttons. There is also a humidity sensor somewhere; in the 3-series it's right underneath the rain sensor on the rearview mirror. If it was humid enough, then it is possible that it will blast out heat no matter what unless you turn on the AC compressor (snowflake button). It has a tendency to be more sensitive to moisture than I'd like.

NoQuarter
05-11-2010, 04:06 PM
Good points. But i'm getting the heat with the AC and long after any residual humidity should be around.

I'll keep trying to figure it out.

Jim

ROCKYTOP2
05-12-2010, 06:44 AM
Go into the idrive where the ac controls are and switch the unit from heat to ac. It is in between the fan controls of driver and passenger. There are 4 bars for cold 1 grey for neutral and 4 for hot.

cac3a
05-12-2010, 06:50 AM
I have somewhat similar problem as to get the auto temp to work for me. In my case I haven't noticed the temperature change, but what annoys me is that I want more air to come on feet than dashboard. Every time, I hit auto it defaults air distribution to level that screws my settings and auto comes on every single time you turn the engine on. I wonder if there is a way to save the distribution as default.

One thing that just came to my mind is that I've had battery problems as even my cd changer wouldn't hold memory of what cd and track was played. Now that I have a new battery, I need to check if the air flow distribution is saved because last track and cd is saved...

NoQuarter
05-12-2010, 08:20 AM
I'm pretty sure I have it switched from heat to ac in the auto setting menu correctly - that's why I feel the cold AC from the dash. I'll check it out again when I can get back to my car.

I also don't care for the automatic distribution auto selects and likewise when I switch to manual those settings are whatever the auto was as the time I switcthed - I have not seen it save any manual preferences for the volume of air between dash and feet.

ROCKYTOP2
05-12-2010, 01:30 PM
That is odd. My preferences are saved for air distribution...

jbrunn
05-12-2010, 01:52 PM
By selecting the smaller ventillation knobs to the left and or right of center(auto) knob, it will default to whatever was setup in the manual distribution mode. I find that pretty handy living in Minnesota where in the winter I might need more "uplift" for the windshield to keep it clear. Conversly in the summer I can push more cooling to the floor vs what "auto" mode provides.

porshah
05-12-2010, 02:36 PM
OP...I understand what you mean. The word "Auto" to me means just that!...why do I have to go in to iDrive to change from Hot to Cold? Very strange. In my previous Audi and VW it worked exactly as it should. If I set the temp to 71...it got to 71 without any interaction from me.

PimoX3
05-13-2010, 08:31 AM
OP...I understand what you mean. The word "Auto" to me means just that!...why do I have to go in to iDrive to change from Hot to Cold? Very strange. In my previous Audi and VW it worked exactly as it should. If I set the temp to 71...it got to 71 without any interaction from me.

Hmmm... how to describe... BMW (virtually all models that I'm familiar with) have an additional control that controls the 'relative' heat from the dashboard vents - even it auto mode. This is the rotary knob/dial in older models, and the red/blue bar control in iDrive for our 5-series.

If you want relatively even heat distribution, leave this control in the neutral (single gray/white bar) position.
If you prefer warmer air hitting you directly in the face/chest, set this control to red positions. In the summer this means you won't get the coldest AC right in your face, which some people find uncomfortable. The car will still attempt to maintain the set temperature, but won't blast you with the cold air from the dash vents (it will be directed to other vents)
If you prefer cooler air hitting you directly in the face/chest, set this control to blue positions. This can be useful in the winter when having the hottest air directed at you (while wearing a winter coat) might not be that comfortable...

For most people in moderate weather zones, set this to the middle position and don't mess with it. When the AC is on the dash vents will blow cold air, and when the heat is on they will blow hot air. It's when this setting is set all the way hot or cold when the car "appears" to be doing strange things with heat/cold to the various vents, when in fact the car is just attempting to respond to the preferences you've set...
__________________________________
2008 550i M-sport (now with SAT + paddles :thumbup:)
2006 X3 2.5i
1998 528i (retired)

Ndokiss
05-13-2010, 02:31 PM
I set the temp to about 68 in the cabin. When the cabin needs to be cooled I feel the cold air from the dash as I would expect - but I get heat from the windshield defrost and heat in the foot well. This is on a sunny day with the sun heating me up and then I have to put up with heat hitting me from the defrost and feet! Is this what others experience?

Jim

I had the same problem you had 2 years ago. There was always hot air coming from the footwell. The hot air from the window vent will always be warm; that is normal. I took the car to the shop, they told me that I had a bad water valve in the A/C system. Since I was out of warranty, parts and labor = $395. It fixed the problem with hot air from the footwell and now, the air to the footwell varies from hot to cold based on cabin temp settings. It also increased the air to the rear passengers through the fron armrest.

clspruiell
11-04-2010, 09:35 AM
i call for getting rid of the rotary dial thing in the middle. i mean alot of people i know dont even know how to use the Auto function on the AC. I find this knob confusing, unneccesary, and a nucance (ms?). Holy crap i just went and bought my tag! Who was surprised?

x3ronnie
11-04-2010, 10:46 AM
I have somewhat similar problem as to get the auto temp to work for me. In my case I haven't noticed the temperature change, but what annoys me is that I want more air to come on feet than dashboard. Every time, I hit auto it defaults air distribution to level that screws my settings and auto comes on every single time you turn the engine on. I wonder if there is a way to save the distribution as default.

One thing that just came to my mind is that I've had battery problems as even my cd changer wouldn't hold memory of what cd and track was played. Now that I have a new battery, I need to check if the air flow distribution is saved because last track and cd is saved...

This seems to be a problem for me too. I cannot get the car to leave my last settings alone (for climate control) on start up. I have given up.

clspruiell
11-04-2010, 12:14 PM
hm mine will stay where i left them. but to change them, i have to rotate the driver knob to my temp. then the passenger knob. . then ensure that the hot/cold thingie is set right too. its a process. again, most people i know dont even know how to use the regular Auto mode properly (my mom and gf). Ha it kills me. They still use it the old fashioned way.

clspruiell
11-04-2010, 12:15 PM
btw, my mom and gf are two different people. that wouldnt be proper even here in alabama.

NoQuarter
11-04-2010, 12:39 PM
btw, my mom and gf are two different people. that wouldnt be proper even here in alabama.

Thanks for making that clear! :p

JeffVander
11-04-2010, 10:23 PM
NoQuarter,

I think you're just going to have to adopt an attitude of Zen about the climate control system. This is my 5th or 6th BMW now and the auto climate controls all have their quirks.

1) The temperature on the dial is not actually accurate. 68 degrees doesn't actually get you 68 degrees in the cabin. And yes, it will blow cold air out of the face vents as a result. Rotate it higher until you get a temperature number that suits you.
2) Even on Medium Intensity, the system will blow pretty hard when the car starts if the temp. difference is high enough. Why? No clue.

I've just learn to adapt to each one of them as I change cars. Either that or get a Lexus because my wife's RX is just about perfect with its climate control.

clspruiell
11-05-2010, 07:39 AM
ha yeah, my saab is great about temp too. and it automatically turns onthe seat heaters to whatever level it feels fit depending on the temp.. kinda cool.. although to many men that can be annoying. but they go off as it gets warm.

anyway, yeah ive always felt bmw's climate control was unintuitive. i just wonder who at bmw created this very nice complex system and said "yep this is perfect guys, place it in production!"

legend700
11-05-2010, 07:59 AM
Right after getting the car in the middle of summer we took a 3,100 mile trip over 10 days from SC to Maine and back. Put climate control on automatic and enjoyed the ride. From 70s in the NE to high 90s in the South we were always comfy; except when we got stuck in traffic around Boston (coming ang going) when the fan speed was set from low to medium in iDrive to increase air flow. I admit, the interface could be more intuitive.

TerraSlug
11-05-2010, 09:03 AM
PimoX3, thanks for that post. That explains my issue last night- it was the first time I've needed heat in my recently purchased car. Both temp knobs were set on about 74 and I only felt cool air from the dash vents. When I got out to refuel I realized the car's interior was warm, but the dash air, blowing directly towards my chest/face was still cool. Now, after reading that post, I'll set the iDrive red/blue bar control to neutral or red- I now remember that it was set to a blue position the last time I checked it.

Hmmm... how to describe... BMW (virtually all models that I'm familiar with) have an additional control that controls the 'relative' heat from the dashboard vents - even it auto mode. This is the rotary knob/dial in older models, and the red/blue bar control in iDrive for our 5-series.
...
For most people in moderate weather zones, set this to the middle position and don't mess with it. When the AC is on the dash vents will blow cold air, and when the heat is on they will blow hot air. It's when this setting is set all the way hot or cold when the car "appears" to be doing strange things with heat/cold to the various vents, when in fact the car is just attempting to respond to the preferences you've set...
__________________________________
2008 550i M-sport (now with SAT + paddles :thumbup:)
2006 X3 2.5i
1998 528i (retired)

Yukon2008
11-05-2010, 10:03 AM
The climate control is by far the worst feature on my 2008 535xi. As seasons change, you have to continually go into idrive to change from the blue to the red bars and back, or leave them on 1 red bar and use the MAX AC button to overide when you need it cooler.

At least I can get some entertainment watching people in the passenger sear try to adjust their temperature when they're too hot or cold!