I am wanting to install a solar powered vent fan in the roof but don't want unfiltered air coming in. Is the fresh air inlet at the front of the MCI9 filtered? What about using the ac filter for fresh air inlet{ac system removed}? Thanks for all the help. Jim
If you mean the one that comes in under the windshield, no, it's not filtered.
There is also one in the door.
I think you'll find that these coaches leak so much air, it's not going to be easy to keep unfiltered air from coming in, if you are exhausting with a roof mounted fan.
It might be possible to install a filtered air inlet, but I've not seen the need for it. Maybe you or someone in your family has more problems with unfiltered air, in which case I'd look at maybe modifying one of the side fresh air intakes for the old coach HVAC system, and installing a filter over that. Wouldn't be too difficult to do.
craig