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Discussion Starter · #1 · (Edited)
I've had my X5 for about 6 months, and all is well, except I really would like to know if the A/C is really auto? I do have the Premium Pkg, so I have dual digital control. The fan speed works fine, adjust down when it gets cooler in the car, but at night when things really don't need full cooling, and a mixture of warm air is needed to keep the interior at 74 degrees, I get NO warm air, EXCEPT, if I adjust the middle vent knob to somewhere in the one/blue one/red setting - like in the middle of the range. When it sits in the sun, and I need MAX cooling, I have to manually adjust the control to 3-Blue dots so I get max a/c.

So is this normal, or should I get re-warmed air when the system has fully cooled the interior down without any twidling of the center vent warm/cool control? In previous cars I've had with AUTO Climate Control, the system would do whatever it needed to keep the interior at the temp you set on the console. This includes adding warm air to the cooled air to maintain the temp.

You wouldn't think we would need any warming here in South Florida, but at night when the sun goes down, it can get very chilly in the car without making the adjustment.
 

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RetiredBum
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No HVAC xpert here, but my understanding and anecdotal usage shows me that:
-the center vents/face level vents' temp is really modulated by that red/blue dotted/adjustable wheel.
-when parked in hot sun, the A/C will not go to "max" as that automatically recircs the interior air which is usually even hotter than ambient outside temps...it will "wait" awhile before it allows sys to go to full Max.

As I don't live where we operate huge amounts of A/C and do Not run X'x HVAC sys on Auto, ever,
I may be way off base here. The Manual is not really clear on some of the settings, either, imo.
But, my 2cts. GL, md
 

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Auto A/C???

Phil:
The BMW (unlike other luxury cars) A/C is not really fully auto as 1) it will not turn on automatically when more cooling is required than available from the outside air - you must do that by manually pushing the a/c button to get additional cooling and 2) the system will not mix or blend the air to all outlets to best reach and maintain desired temperature (you must manually adjust blend of air to the top vents to select outside or inside air source. :dunno:
 

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Discussion Starter · #4 ·
Hmmm, not so automatic

Guss,
Your explanation confirms my experience. So I'll continue to rotate the center vent dial as we need more warm than cold. Strange that all other functions are auto except for the re-mix of warm air to maitain a set temp.
Thanks,
 

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X5 "Auto" AC is not really automatic

Phil,

I can confirm the need to adjust the dial between the red and blue dots once the car is cool. I have been adjusting the wheel and the fan speed for 5 years despite the fact that my X5 has an automatic climate control set to 68 degrees. No matter what temp I set, the fan speed only decreases to four bars and with the AC on, it can get awful cold if you don't manually decrease the fan speed or fiddle with the dotted wheel.

How can BMW call this system automatic? Why do I even set a temp if I must adjust things anyway? :dunno:

Bigfoot
 

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Guss said:
Phil:
The BMW (unlike other luxury cars) A/C is not really fully auto as 1) it will not turn on automatically when more cooling is required than available from the outside air - you must do that by manually pushing the a/c button to get additional cooling and 2) the system will not mix or blend the air to all outlets to best reach and maintain desired temperature (you must manually adjust blend of air to the top vents to select outside or inside air source. :dunno:
In that case, what is the point of BMW's automatic climate control...Since you have to control most of the things manually anyway? Wouldn't the simpler manual dials on the standard climate control accomplish the same function? :dunno:
 

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Reading these posts, I am not sure why my system seems different. Maybe I am confused.

I leave it on fully automatic, always. I have used the defrost occasionally, in just over 2 years with the X5, but 99% of the time it is on automatic.

Mine maintains the temperature fine, no problem at all. I adjust between 19 C and 20 C on the left, 20 and 21 on the right, depending on preference, those are my primary adjustments.

I use the thumbwheel on the upper vents to adjust the vent air temp, to vary it from the temperature set on the dial. I recall reading that each red or blue bump corresponds to 1 degree variation, hotter or colder, from the temperature set on the automatic setting, and only for the top centre vent. This is to allow the car to be warm, and for me, to have cooler fresh air on the face. I don't believe that the thumb wheel has anything to do with mixing inside and outside air, it just bumps the setting up or down slightly, thus it is mixing warm and cold.

The fan speed never goes below a certain level so that there is always air moving in the vehicle, keeping it fresh. Important for me, as I only ever have a window open to use a parking access card.

I leave it on automatic recir, so that if contaminants are sensed by the system, it goes to recirc.

That's it. Never had any problem with it. It certainly seems fully automatic to me, since the temperature has been correct for 2 years, through very different climatic conditions (from snow, through 32 C)

But again, maybe I am just confused.
 

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Discussion Starter · #8 ·
I'm confused too

Hi jcl10,
Here is an Auto Climate Control System that knows enough to change to INSIDE air if the outside air gets dirty, but can't remix warm air to maintain inside temp :mad:

Next trip to the dealer I'll have to ask them to explain this to me - although I won't expect much of an answer. I was wondering if they had any diagnostic tools to know if the system is working correctly.
 

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just copacetic!!!
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jcl10 said:
Reading these posts, I am not sure why my system seems different. Maybe I am confused.

I leave it on fully automatic, always. I have used the defrost occasionally, in just over 2 years with the X5, but 99% of the time it is on automatic.

Mine maintains the temperature fine, no problem at all. I adjust between 19 C and 20 C on the left, 20 and 21 on the right, depending on preference, those are my primary adjustments.

I use the thumbwheel on the upper vents to adjust the vent air temp, to vary it from the temperature set on the dial. I recall reading that each red or blue bump corresponds to 1 degree variation, hotter or colder, from the temperature set on the automatic setting, and only for the top centre vent. This is to allow the car to be warm, and for me, to have cooler fresh air on the face. I don't believe that the thumb wheel has anything to do with mixing inside and outside air, it just bumps the setting up or down slightly, thus it is mixing warm and cold.
:stupid: This has always been a feature of BMW's, at least since the E21 series IIRC. I like it because I can direct cooler air to my face while the rest of the interior temp is set warmer.
 

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Discussion Starter · #10 ·
Hi Dan,
If adjustment of the center vent temp control is normal, then it sounds like my system is working correctly. I'm just confused that in other vehicles (yeah I know, this is NOT like any other vehicle) when you set a temp, the system modulated the center air and remixed warm air to maintain the desired temp in the cabin. If the Auto mode selects the right vents to discharge the air, Top Vents, Bottom Vents, Front Window, then you would expect the air coming from that vent to be remixed as well, not have to fiddle with the center vent controls.
 

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phastphil said:
Hi Dan,
If adjustment of the center vent temp control is normal, then it sounds like my system is working correctly. I'm just confused that in other vehicles (yeah I know, this is NOT like any other vehicle) when you set a temp, the system modulated the center air and remixed warm air to maintain the desired temp in the cabin. If the Auto mode selects the right vents to discharge the air, Top Vents, Bottom Vents, Front Window, then you would expect the air coming from that vent to be remixed as well, not have to fiddle with the center vent controls.
Phastphil,

I think the confusion over the "auto" button is that one has to depress the button so that the word "auto" shows in the display. The green light on the button is on all the time, I think so that the button shows in the dark. My daughter was the one who alerted me to this - when in auto mode (display shows "auto"), the climate control system will put out cold air or hot air to the interior vents (not the center vents which one controls manually) depending on the temperature you set. On a hot day when starting the car, the system automatically kicks into maximum cold mode and on a cold day, I can feel the warm air coming from the interior vents. The nice thing about manually controlling the center vents is to allow cool air to blow on your face while the rest of the interior is kept at a warmer temperature.

Hope this makes sense!
 

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phastphil said:
Hi Dan,
If adjustment of the center vent temp control is normal, then it sounds like my system is working correctly. I'm just confused that in other vehicles (yeah I know, this is NOT like any other vehicle) when you set a temp, the system modulated the center air and remixed warm air to maintain the desired temp in the cabin. If the Auto mode selects the right vents to discharge the air, Top Vents, Bottom Vents, Front Window, then you would expect the air coming from that vent to be remixed as well, not have to fiddle with the center vent controls.
Actually i thought automatic was not working as well but i was
wrong. I don't know all the technical terms but I found out
that in auto (air conditioning on ) mode the temp adjustment up or down determines cabin temp and fan speed. I found that if the outside temp is 75 and you ask for the inside temp to be 69 the system will work to achieve that cabin temp based on the outside temp. But if i drive to another area (We have Micro climates here) and the temp outside drops below the 69 degree point i've selected in the cabin the fan speed will drop and the air from the vents will warm slightly to compensate for the outside temperture provided both side are set to the same temp.

If the passenger side is set to say 72 degrees you get heat from only those vents on the passenger side if the outside temp is lower. If the drivers side temp is lower than the outside temp the system will deliver colder air to the driver.

To me that center vent temp control seems to work "blue in the summer" and "red in the winter". I'm not an expert but so far that's been my experience.
 

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The BMW automatic HVAC system works as described, changing fan speed and temeprature according to the set contol temperature, measured interior temeprature (little vent holes near A/C controls), and the outside temperature.

The automatic recirculation button acts to close the outside fresh air inlets when particulate matter is sensed near the microfilter (like diesel soot or heavy road dust). It does not sense odors. This closed recirculation vent is opened after a set amount of time when in the auto mode to prevent fogging of the interior windows (when raining) and to prevent driver fatigue by resupplying fresh outside air.

The "fixed" recirculation mode will not automatically reopen the outside air vent until disengaged.

The temperature control dial (blue-red dial) on the center vent will provide adjustable temperature above or below the temperature set point on the interior contro panel. The feature of colder air coming out of the center during heating requirements is a "German" feature on Mercedes and Audis (possibly VW also). The purpose is to prevent driver fatigue and sleepiness during long drives by allowing cool air to douse the body and face and thereby providing a more alert driver.

This is how I have learned the system performs on my year 2000 328i Other years may have slightly different characteristics due to upgrades such as where the interior temperature sensor is placed, or the addition of a sun angle sensor above the dash to direct colder air on the sunny side of the interior.
 

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My last car was a VW W8, all I had to do was set it and forget it... I hope BMW addresses this in the next X, seems kinda redundant to me.
 

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Discussion Starter · #16 ·
Thanks all for the data/info. The amazing part of all the response on this thread is the different ways people use the Auto Climate system. I have friends with luxury type cars that set the temp at min. usually 60 and control the fan speed. I'm a "use technology" kind of guy, so I think it's "cool" to set the temp and wait for the system to do its thing. But here in SF, we very rarely use the bottom vents, as the temp is always hot and the A/C is on year round, so the air is always coming from the top vents. I guess this is where I've got into trouble, since the air from the top vents basically is controlled by the center vent temp control.
 

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DaveH said:
The automatic recirculation button acts to close the outside fresh air inlets when particulate matter is sensed near the microfilter (like diesel soot or heavy road dust). This closed recirculation vent is opened after a set amount of time when in the auto mode to prevent fogging of the interior windows (when raining) and to prevent driver fatigue by resupplying fresh outside air.
One thing that frustrates me about both my BMW's relates to the recirculation... At highway speeds, with the recirculation set on fresh air, the volume of air coming through the vents increases with speed (a terrible design in my opinion). If you put it on Auto-Recirc, then occasionally it will close and open - seemingly at random since there is no obvious reason I can see for it to be closing (i.e. heavy diesel, etc.). So the effect you get while driving down the highway is random blasts of outside air coming at you (regardless of fan speed). This is most annoying and noticable when you are on the highway for an hour or more. It's rediculous. Airflow moderated by vehicles speed was something I thought I got rid of with my 80's cars.
 

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phastphil said:
But here in SF, we very rarely use the bottom vents, as the temp is always hot and the A/C is on year round.
Interesting. When you say the temp is always hot are you refering to the weather?
or engine temp? If your refering to the weather then your one of the few who thinks
the temp is always hot. Personally I like this quote "Finally, two pieces of advice -- never call it "Frisco," and remember what Mark Twain said: "The coldest winter I ever spent was a summer in San Francisco." Dress in layers! :)
 

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Quicksilver said:
Interesting. When you say the temp is always hot are you refering to the weather?
or engine temp? If your refering to the weather then your one of the few who thinks
the temp is always hot. Personally I like this quote "Finally, two pieces of advice -- never call it "Frisco," and remember what Mark Twain said: "The coldest winter I ever spent was a summer in San Francisco." Dress in layers! :)
By SF he was referring to South Florida.
 

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I think BMW's "automatic" climate control is the best I have tried. I really like little "wheel with dots" that controls the cool/warm flow.

I runs circles over my premium Nissan "automatic" climate control that can't ever seem to make up its mind!
 
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