A big part of the ventilation strategy on my van is the Fan-Tastic vent/fan combination. A lot of RV's have these because they're well made and, even after the buyout by Atwood, the company is very responsive to the needs of it's customers, right down to the occasional free replacement part. I don't have the remote control option because - well - the fan is always pretty much within arms reach anyway, but my fan has all the other bells and whistles, including a rain sensor to shut the vent for me when I've wandered off and left it open.
Which I do a lot; leave it open that is. Anywhere from a month at a time in the driveway between trips* to a few minutes in the parking lot when running into the store for a
Today was one of those whiles.
The vent, as usual, was already open and switching the fan speed to zero also disables the closer motor so when I get the sensor all wet and rainy-like the cover won't close on my hand like a pissed off, though really slow, clam. The van is tall and it takes my largest step ladder to get up high enough, but once there all it takes is a little soapy water and a bit of scrubbing.
As long as I'm there I give the rest of the fan a good cleaning and, for good measure, give the solar panel gets a swipe or two as well.
Safely back on the ground (Man it's a long way up there!) I turn the fan speed back to 1 and test the up-down motor then mark the calender to remind myself to repeat the process again in about 6 months.
*I always drive the van somewhere at least once a month, trip or not, to make sure everything stays limber and operational. I also fire up the second most complex mechanical device, the fridge, at the same time.