Worn out buttons, WTF?

I too have to say the HVAC system in my car is the best I've ever experienced; I almost always leave it on mid-range auto at 70 and the temperature and fan speed is always perfect! If cold out, I dial up to 84 and if hot out down to 60. I never shut off the compressor (it's double switched anyway, knowing when and when not to engage). I also have climate comfort glass.

Originally Posted by dbs600

If cold out, I dial up to 84 and if hot out down to 60.

Moving the temperature manually to very hot or cold will not affect heating/cooling speed. The system will automatically utilize max cold or heat as needed (along with faster fan speeds) to bring the cabin to the set temperature as quickly as possible. The air temperature, and fan speed, will moderate automatically as the cabin reaches that point.

Originally Posted by markl53

Moving the temperature manually to very hot or cold will not affect heating/cooling speed. The system will automatically utilize max cold or heat as needed (along with faster fan speeds) to bring the cabin to the set temperature as quickly as possible. The air temperature, and fan speed, will moderate automatically as the cabin reaches that point.

Exactly; I rarely change the fan/blower speed and most always leave it on mid-range auto, where the system does the rest. One of the few positives that has really exceeded my expectations (better than my experience with Mercedes-Benz, Land Rover and Lexus).

Originally Posted by markl53

Even though the "AC", or snowflake, button is lit, the system will not run the compressor below a certain ambient temperature. You can leave the button "on" all the time. Also, in heating season, the air can be moist, causing windows to fog. Leaving the compressor engaged will dry the air and avoid window fogging, even without the use of the defogger setting for heavy windshield fog. In fact, I never run the defrost function specifically, never find the need. In some fog-producing weather, I do take manual control of the fan, and possibly air distribution mode (floor + windshield), to ensure sufficient air movement in the cabin to keep the windows clear. Don't you often see cars with fogged windows in cold weather? Actually, more often than not, they are "lower class" cars that I notice. The drivers obviously don't know to turn on their compressor even when using heat. Another observation you may not have noticed on many climate systems -- as the cabin temperature moderates in cooler weather, the air delivery vents usually switch automatically to floor/windshield to deliver some cooler air toward the upper part of the cabin. By using the windshield vents, the system can avoid blowing cool air directly at the occupants while maintaining an overall comfortable setting.

However, if you are doing the fresh air "vent" thing, then yes, I turn off the snowflake. In that case I usually go to full manual to avoid the fan blowing faster and faster, trying to cool the car (if it's hot outside).

Great info. Okay, so the system is smart enough to know when to apply the compressor even when A/C is on, good to know. So you guys are saying that on a BMW, having the compressor on at all times robs absolutely NO power and MPG (like it does on pretty much any "normal car")?

Oh, and what does the "A" and "M" mean on the air-recycle button. I figure "Auto" and "Manual", but does it basically mean that it'll figure out for itself when to recycle the cabins air (as opposed to bringing in outside air) if you have it clicked to "A"?

Originally Posted by K-A

Oh, and what does the "A" and "M" mean on the air-recycle button. I figure "Auto" and "Manual", but does it basically mean that it'll figure out for itself when to recycle the cabins air (as opposed to bringing in outside air) if you have it clicked to "A"?

Yes. A means it will automatically decide when to recycle the cabin air. M means it is recycling the cabin air because you told it to.

-Corey

Originally Posted by cordoor

Yes. A means it will automatically decide when to recycle the cabin air. M means it is recycling the cabin air because you told it to.

-Corey

Pretty much. However, even in "no" mode (neither LED lit), the recirculation mode will be enabled "silently" if maximum cooling is needed. The "A" position is supposed to detect "noxious" fumes and the like, and turn on the recirc mode by itself.

Originally Posted by K-A

Great info. Okay, so the system is smart enough to know when to apply the compressor even when A/C is on, good to know. So you guys are saying that on a BMW, having the compressor on at all times robs absolutely NO power and MPG (like it does on pretty much any "normal car")?

I'm not sure anyone said running the compressor won't affect engine output. I believe it will. However, and even your MB worked this way, German cars use variable output compressors -- you won't hear the constant clicking on and off that other cars do. Basically, the compressor clutch is engaged once just after the car is started, and it is engaged all the time after that (when snowflake button is "on", and except for very cold ambient temps mentioned earlier).

Oh, and what does the "A" and "M" mean on the air-recycle button. I figure "Auto" and "Manual", but does it basically mean that it'll figure out for itself when to recycle the cabins air (as opposed to bringing in outside air) if you have it clicked to "A"?

See responses above.