Palmo

Hi Folks,

This is something I've been meaning to ask on here for a while. I've owned my car from new since April 07. However, after 19 months of ownership I am still baffled by one of the heater functions.

Basically, no matter what setting I put the heater on e.g both temperature knobs to 'cold', with aircon on and the face vent temp set to cold in iDrive, if I have the vent set to windscreen it continually blows 'hot air'. I am able to alter the temperature of the face vents and foot-wells, but no matter what I do, the windscreen and dash top side-window vents continue to blow 'hot air'. This becomes annoying, because if I shut the windscreen off, quite soon it, along with the side windows begins to steam up during winter months. This leaves me with the windscreen vent blowing hot air, and having to have the face vent blowing 'cold air' in order to remain at a bearable temperature.

Also, as a side issue, I find the rear vents only ever blow cool air despite adjusting the temperature control knob in the back.

Advice really appreciated! Do I have something wrong with the car or am I stupid and doing something wrong?

Rudy

The windshield defroster is designed to blow heated air to the windshield since this is the most effective way to remove the condensation. (Using the A/C is a trick that works more quickly but the fog usually returns much quicker too.)

If your windows are fogging up constantly, I'd double-check to see if you have the fresh air vent open or closed. If it's closed, you'll fog up more often.

Do you have the professional/high climate control system or the basic one? If you have the high system, my advice is to use the full automatic settings (including the automatic fresh air vent) and only use the defroster as needed...

Phantom Mark

I noticed the rear vents only blow cold on mine regardless of setting as well actually....................

The hint with full auto btw.........is this the absolute quickest way to get some heat into the car in these winter months ??

TIA

Rudy

I've always used full auto (and simply dialed up or down the temperature dials to make adjustments) and have zero issues with climate. Although the car heats up pretty quickly, the heated seats and steering wheel provide some relief during the short time it takes for the system to blow warm air.

One more thing to check if you still have fogging problem on the windshield...clean the inside of it! Often times when a windshield has a film buildup on the inside, it fogs much more often...

Palmo

Thanks Rudy for the super quick reply!

Are you saying that the windscreen defroster only blows heated air and that this can't be changed? I do find that once the car is up to temperature, if I drive 'without the windscreen defroster' blowing (only on low) then the windows quickly begin to fog up - TBH I find this to be the case on most modern cars fitted with aircon / climate. The trouble is, the heat being emitted to the window, soon swirls back into the cabin and causes the atmosphere to be 'too warm' for my liking. It would be ideal if I could reduce the temperature being emitted from the window vent - but if not, then I guess I'll have to live with it.

I do have the professional / extended feature climate control system, but must admit to rarely using the auto function.....maybe I need to get into using this and familarise my self with this!

Why are the rear vents always cool?

Cheers

Rudy

You're trying to solve a problem that isn't the problem. Making the windshield vents blow cooler air might sound like what you want to accomplish but in reality, you need to prevent the windshield from fogging in the first place. The professional (high) climate system in the car is quite advanced and should not allow the windows to fog in most cases. As soon as you start to override the automatic systems, unless you're able to adjust things constantly like the computer can (and does), you run the risk of excess fogging, uncomfortable temperatures, etc. As I've said in posts before, I'm a firm believer in using the automatic mode and simply dialing the temperature up or down as desired to keep things comfortable. Too many people, when warm or cold, start messing with the fan speed or the vent settings and end up on a "roller coaster ride" of climate change where they never seem to catch the "sweet spot" and get locked on to a comfortable cabin. Remember, as soon as you touch the fan knob or vent settings, you're no longer on automatic so you've assigned the burden of constantly adjusting things to yourself instead of the computer.

Take a look at the following related thread:
http://forums.e60.net/index.php?showtopic=36116

Also, there is a document in the technical gallery that gives you a bunch of technical details about the climate system:
http://forums.e60.net/index.php?autocom=ga...si&img=6497

Good luck!

LW78

Does the windshield vent also blow only hot air when it's in 'Auto mode'? If you push the button showing on attached photo, it will only blow hot air!

As Rudy already stated, the 'Auto' mode is the best mode to use.

Palmo

Thanks again Rudy.... I will take your advice and give the auto mode a good try and see how I go and resist the temptation to 'know better' and try and override it. Will let you know how I get on!