I ordered one of these last night and when it gets here I'll finish this review.
http://www.campingworld.com/browse/s...src=WL&rewrote
This is designed to replace/upgrade those horrible little fans that sometimes come in RV ceiling vents. Removal of the exterior dome/lid is not required to install the Vortex fan upgrade. You just remove the interior garnish and the old fan and replace with this one. If there is no fan in your vent, the 12 vdc wiring is almost always provided by the RV factory. You just need to figure out how to attach the wiring to the fan.
Visit the junk box, I suppose.
I went with this option to improve circulation and heat control, choosing this product over the more expensive Fan-tastic style fan options for two main reasons:
1. I don't have to get on the roof and rip out the old vent. Or my paid for Maxx-Air covers.
2. The Vortex fan only cost $51 on sale at Camping World.
Assuming the 12 vdc fan option wires are in fact where they should be the install should take less than an hour. We'll see when it gets here.