Finally, after years of suffering through the original roof vent that had a mind of it’s own when the morning dew fell on the rain sensor, closing the roof vent, then opening it, then closing, then opening, etc., I decided enough was enough and got the MaxxFan 7500K.
My brother Mark and I installed it. It was not too bad, except for removing all the old caulk. It works very well. I can leave the roof vent open all year now even while the Airstream is in storage or on the road, come rain or shine. It also has a remote where you can set the desired temperature and many fan speeds. One can also reverse the fan to blow air down into the Airstream.
I’ve been very happy with the switch, since I no longer need to worry about the erratic roof vent. Now, when going for a hike I don’t need to close the roof vent incase of a rain shower (since I never trusted the rain sensor). Here is more info on the MaxxAir company website.