Upon start heat comes on ?

E70x5 · #1 03-10-2010, 12:50 PM

I know the heat comes on automatically in the winter upon starting the car. Does it come on automatically in the summer too ? Does it
sense the temperature and know when AC or heat is needed ? I bought the X this winter and haven't driven it in the summer yet. This is quite annoying because the car hasn't warmed up yet, wish this was a feature u can turn off and on. . .

rh71 · #2 03-10-2010, 03:15 PM

If the engine was off for 15 or 20 mins (I forget which), the fan comes on even if you had shut it off. The temperature which you left it at will be the same though... so it's not actually heat on... it's fan on, at whatever temp you had it at. There does not appear to be a way to keep the fan off at startup.

E70x5 · #3 03-10-2010, 04:04 PM

Thanks for the info rh71 !

deutsch100 · #4 03-10-2010, 04:14 PM

The dealer told me it is a factory set feature, that cannot be disabled (as rh71 said). The factory deemed it necessary for ventilation (frische Luft auf Deutsch

. It is annoying that one cannot turn it off, as in other BMW models though.

RedRockin · #5 03-10-2010, 08:26 PM

Quote:

Originally Posted by E70x5

I know the heat comes on automatically in the winter upon starting the car. Does it come on automatically in the summer too ? Does it
sense the temperature and know when AC or heat is needed ? I bought the X this winter and haven't driven it in the summer yet. This is quite annoying because the car hasn't warmed up yet, wish this was a feature u can turn off and on. . .

Actually, I believe the details may be a bit more clarified. Yes, the fan does come on when you turn on the vehicle. If you had turned the climate system off (fan lower button until screen goes off) and restart the car within the designated time (10, 15, or 20 minutes - who knows?!) the climate will be off, otherwise (longer than ...) the fan will come back on automatically. However, "heat" seems to be merely a function of the set temp being higher than the exterior air temperature. For example, if your external temp is 68 degrees and you have the climate set for 60 degrees, when the system comes "on" at startup - you should (I think) only get fan. If the external is 60 and climate is set at 68, you should (I do) get heat.

Alternatively, if you have the "auto" button engaged, the climate system should (theoretically - some claim the snowflake must be illuminated) endeavor to maintain the set temp using heat or AC as needed. If the AC button is not illuminated, you (theoretically) should not be actually running AC and your compressor. In addition to all of this, you also have your recirculation button which also has an automatic setting, manually forced recirculation, and external air setting (should be green left, green right and no light respectively - I think).
There is another thread (today) arguing the features of the climate system. http://www.xoutpost.com/bmw-sav-foru...full-auto.html I do not completely agree with all stated therein but I live in a different climate and am new to BMWs. They recommend setting the Auto temp, illuminating the snowflake and leaving it pretty much permanently. Where I live, for at least 6 to 8 months of the year I do not want any heat or AC blowing - only fresh air and/or open windows/roof. So I plan to probably never use the Auto feature. If I want AC I'll set the temp and hit the snowflake - I am assuming this will manually turn on AC and maintain the set temp. If I want heat, I'll leave the snowflake off and just raise temp to where I want it. If I want max I'll hit the recirculate button. I will probably never use the automatic recirculate feature. Where I live it is so dry most of the year I do not need my car to dehumidify the air.

It is a complex system - many others are much easier to use. It is not particularly intuitive - unless you think in German

I suspect the primary reason we see climate in iDrive is that it probably needs to be there for the voice activation features. Then again, I've only had my very first BMW for just over a month now. The other thread is a discussion between much more experienced BMWers. Check it out and see if anything there is more helpful.

rh71 · #6 03-11-2010, 09:03 AM

One thing I'll mention about the auto feature for the heat... if they rely on sensors, etc... you never know when the a/c is on when you don't want it to be... just like when our headlamps are on at 4pm with the sun out sometimes.

JCL · #7 03-12-2010, 03:00 AM

Quote:

Originally Posted by rh71

you never know when the a/c is on when you don't want it to be... just like when our headlamps are on at 4pm with the sun out sometimes.

I would have thought that the E70 is the same as the E60 in regards to automatic headlights, since it is based on the E60 platform. When my auto headlights illuminate, there is a green LED lit up on the headlight switch. Does the E70 not have that LED?

rh71 · #8 03-12-2010, 09:39 AM

Quote:

Originally Posted by JCL

I would have thought that the E70 is the same as the E60 in regards to automatic headlights, since it is based on the E60 platform. When my auto headlights illuminate, there is a green LED lit up on the headlight switch. Does the E70 not have that LED?

It does, and the instrument cluster turns orange - that's how we know it's on... but at 4-5pm when the sun is still prominently shining (although setting) it sometimes comes on and it doesn't appear consistent... wacky sensor they're using.

autoque · #9 03-12-2010, 11:57 AM

You know something? When it's on Auto, the A/C light is automatically turned on, activating the compressor, and when I turn that off, Auto shuts down. So basically if you are using the Auto feature in winter, it's giving hot air but it's also cooled with the compressor first. Quite a waste of fuel and energy. It does say in the manual that doing so will blow drier air by cooling the air w/ the compressor first, but A/C saps a bit of horsepower from the engine. So I never use Auto button at least in winter.

Penguin · #10 03-12-2010, 02:50 PM

Quote:

Originally Posted by autoque

When it's on Auto, the A/C light is automatically turned on, activating the compressor

No.

Having the A/C light on does not mean the compressor is activated. It means the compressor may be activated if the climate control determines it should be, e.g., if you have the auto temp set at 78 degrees, the outside air is at 45 degrees, and you do not have the defroster setting turned on, the A/C compressor will not be engaged, even if the green light on the A/C button is lit.

If you have the defrost setting activated, the system will activate the A/C, as it assume you would like to be able to see through the windshield ASAP, and dehumidified air will clear the windscreen faster.