michakaveli

What does this feature do?

'97 E300

awiner

When on, the airflow comming into the vehicle is passed through an 'activated charcoal filter', thus, removing odors and such.

michakaveli

Is it ok to have it on all the time? I know there is a filter for it...

awiner

It is not recommended to have it on all the time. Only when needed. Supposedly it will reduce airflow and heating up or cooling the interior vehicle will be effected. I also believe it will shut off after so many minutes.

mbtech208

Adam's right, plus activating the filter also inhibits the ability of the air conditioning system to dry the air, so the windows may fog up if the charcoal filter is left on too long. The W210 already has 2 dust filters that are filtering the air constantly, so the charcoal filter should just be used to filter odors.

jswedberg

Does the filter "wear out"? I imagine it would lose its effectivness eventually.

I believe it is quite expensive. How do you know when it is time to replace it? When those odors keep on coming?

awiner

Yes the filter does lose it's effectiveness over time with use.

There is a determined replacment interval that your service book should list.