Ventilated seats

[yco]

it doesnt blow anything it sucks air from the surface thats all.. better lower the expectation for easier life..

[heatmizr]

I got a LOL out of this thread! Lots of inquiring minds, and I will keep on checking back for the smoke machine test results

I use this feature a fair amount and MY distinct impression is -
1. The fans SUCK air from the seating surfaces into the seat internals, which must then exit somewhere (below?). Awaiting confirmation via smoke test!
2. Their operation is in no way connected to the Air Condition system. I have run mine with the same results with either a/c or heat activated, for comfort on long drives.
3. Yes they make more noise than actual difference - So I typically don't use them on High very long. too loud in my ears.
4. The effect they provide is very subtle, and not instant. I can feel much more effect on HOT and HUMID days, that is where their benefit is maximum. Helps keep my back from getting moist when getting in a hot car. You may feel little or nothing on cooler / drier days, but may still avoid getting "sticky" on long drive with the sun on you.

I was a bit disappointed with them at first, but now appreciate them for what they are, and wouldn't want to go back to a non-ventilated seat.
Now someone figure out how to BOOST the motor to get them Really Sucking!

[mirob]

Originally Posted by yco

it doesnt blow anything it sucks air from the surface thats all.. better lower the expectation for easier life..

Shit engineering/design since ones body will cover like 95% of the surface area where air is supposed to come from...no wonder they blow (pun NOT intended)...

[Qsilver7]

Guess what I found? Again, my interpretation from the info below is that the BMW ventilated seats "suck" versus "blow" (that is...they suck air "through" the seats versus blow air "from" the seats).

From the BMW technology guide:

Active seat ventilation.

Keeping you feeling fresh even on the longest journey: the active seat ventilation ensures that air circulates throughout the seat constantly, removing moisture and helping prevent discomfort or driving fatigue.

A total of nine axial flow fans are integrated into the high-quality foam padding inside the seat: four in the backrest and five in the seat. The fans draw fresh cabin air into the seats and channel it through an air-permeable middle layer, distributing it evenly throughout the seat. Special perforations in the upholstery allow it to move through the leather, keeping perspiration to a minimum.
The three-speed fans can be controlled using a switch on the central console or a control on the seat itself, depending on your BMW model. The iDrive Controller lets you change the distribution of air between the seat and the backrest. The highest fan speed instantly cools seats that have been heated by direct sunlight, ensuring a comfortable welcome even in summer.
In order to prevent uncomfortable over-cooling of the seat surface, the active seat ventilation includes seat heating, which heats the air to a perfectly comfortable temperature. Long journeys become more comfortable, the driver remains alert and fresh, and - last but not least - clothes are left less creased.

[pdX5M]

Originally Posted by Qsilver7

Guess what I found? Again, my interpretation from the info below is that the BMW ventilated seats "suck" versus "blow" (that is...they suck air "through" the seats versus blow air "from" the seats).

From the BMW technology guide:

Active seat ventilation.

Keeping you feeling fresh even on the longest journey: the active seat ventilation ensures that air circulates throughout the seat constantly, [COLOR="DarkRed"]removing moisture[/COLOR] and helping prevent discomfort or driving fatigue.

A total of nine axial flow fans are integrated into the high-quality foam padding inside the seat: four in the backrest and five in the seat. [COLOR="darkred"]The fans draw fresh cabin air into the seats[/COLOR] and channel it through an air-permeable middle layer, distributing it evenly throughout the seat. Special perforations in the upholstery allow it to move through the leather, keeping perspiration to a minimum.
The three-speed fans can be controlled using a switch on the central console or a control on the seat itself, depending on your BMW model. The iDrive Controller lets you change the distribution of air between the seat and the backrest. The highest fan speed instantly cools seats that have been heated by direct sunlight, ensuring a comfortable welcome even in summer.
In order to prevent uncomfortable over-cooling of the seat surface, the active seat ventilation includes seat heating, which heats the air to a perfectly comfortable temperature. Long journeys become more comfortable, the driver remains alert and fresh, and - last but not least - clothes are left less creased.

The way I read this excerpt is that the fans actually blow air through the seats. If they sucked air then they couldn't have "fresh cabin air" because your ass/back would blocking that fresh air vs. pulling fresh air from below the seat and forcing it though the foam/perforations.

The only part that throws me off a bit is the "removes moisture" part.

[Qsilver7]

Originally Posted by pdX5M

...
The only part that throws me off a bit is the "removes moisture" part.

Perhaps that's because the concept that the fans are designed (exact quote again) "...fans draw fresh cabin air into the seats and channel it through an air-permeable middle layer, distributing it evenly throughout the seat. Special perforations in the upholstery allow it to move through the leather, keeping perspiration to a minimum."...hasn't sunk in yet.

Think of them like a box fan in a window. You can turn the fan to blow air from outside...into the room. Or you can turn the fan to blow air from inside the room...to outside. The BMW ventilated seat fans are turned like in the 2nd scenario.

The "permeable middle layer" is like a plenum behind the perforated surface area of the seats...when your sweaty back is pressed up against the surface of the seat...and the fans are turned on...the "permeable middle layer" allows the circulation of air behind the seat...this helps to reduce the conditions that exacerbates a sweaty back.

[heatmizr]

NINE fans.... I should have seen that coming.
I agree. They suck!

[yco]

cant believe we re talking about this but when it sucks air from the seat surface, it ll remove moisture as it stated and when you remove moisture from a surface it ll get cooler.. and airflow has a cooling effect on objects whether its an ass or a box surface.. thermodynamics..

that phrase is just written by i guess some marketing guy.. cause if air wouldnt be replaced by some other air in the cabin on the seat surface, it would called seat vacuum.. i wouldnt prefer to sit on a seat that sucks my ass..

[Greggo]

Originally Posted by Qsilver7

Guess what I found? Again, my interpretation from the info below is that the BMW ventilated seats "suck" versus "blow" (that is...they suck air "through" the seats versus blow air "from" the seats).

From the BMW technology guide:

Active seat ventilation.

Keeping you feeling fresh even on the longest journey: the active seat ventilation ensures that air circulates throughout the seat constantly, removing moisture and helping prevent discomfort or driving fatigue.

A total of nine axial flow fans are integrated into the high-quality foam padding inside the seat: four in the backrest and five in the seat. The fans draw fresh cabin air into the seats and channel it through an air-permeable middle layer, distributing it evenly throughout the seat. Special perforations in the upholstery allow it to move through the leather, keeping perspiration to a minimum.
The three-speed fans can be controlled using a switch on the central console or a control on the seat itself, depending on your BMW model. The iDrive Controller lets you change the distribution of air between the seat and the backrest. The highest fan speed instantly cools seats that have been heated by direct sunlight, ensuring a comfortable welcome even in summer.
In order to prevent uncomfortable over-cooling of the seat surface, the active seat ventilation includes seat heating, which heats the air to a perfectly comfortable temperature. Long journeys become more comfortable, the driver remains alert and fresh, and - last but not least - clothes are left less creased.

Sorry, this is an old thread. But I have to say something.

Yes, the seats 'draw,' air. Cabin air, from underneath the seat. And "blow," air through the cushion and OUT of the perforations. Not so much you would feel it with your hand, the dispersion is too broad. Not like a concentrated flow from a single vent. Put a thin piece of paper that covers the seat cushion and turn on the seat on high. Does it stick to the seat or float up?

Read the description above. It is very clear how it works.

If the cabin is cooler, and you are wearing thinner cloths, the effects are quite noticeable. Baking hot interior when you first get in on a hot day and it will not feel so pleasant. :-)

I do not have ventilated seats on my current X5, was not on the must have list this go around. Nice feature, would like it again, but it was difficult to find when I was shopping this time. Hardly ever used it. Great on a very long trip in hot country, novelty around town. Keeps your backside from getting sticky.

Just like heated seats, if you are wearing thicker clothing it will not be as noticeable. Especially on the back, wearing a jacket on a cold day.

Thin shorts on a hot day, AC on max, yes it is noticeable.