I don’t want to cut a hole in the roof of my minivan to install a Fan-tastic or MaxxAir fan. Everything I’ve done to convert it into a camper is reversible. I can return the van to stock if need be. Plus, the ceiling is full of lights and air vents I’d have to cut around, and a roof fan would occupy valuable roof space I’d rather dedicate to a solar panel.
The van is well-circulated by a pair of Endless Breeze fans placed in a second row window. When I have the back porch tarp deployed, the fans are protected from rain. I can’t always open the window or deploy the tarp though. On really cold days, I like to keep that second row window closed. In stealth camping situations, the tarp is much too large and conspicuous to deploy.
A roof fan is an ideal way to ventilate in all weather. It doesn’t require a rolled down window or a tarp. Since I can’t cut a hole, I decided to turn the sunroof into a roof fan. I filled the sunroof opening with a sheet of white corrugated plastic and then cut openings in that sheet for four USB-powered muffin fans. The muffin fans are designed for ventilating AV cabinets. They are light and low profile enough that the corrugated plastic surround is sufficient to support them–with help from a 1/4” dowel rod I had laying round.
I wish the fans were reversible with a switch. Changing the air direction requires unscrewing the fans from their chassis, physically flipping them over so that they blow the opposite way, and screwing them back in. I decided to have all four fans exhaust from the van, mainly because I was lazy. I’ll probably change one pair to intake from outside and exhaust into the van to establish a circulation loop.
The flush mount style of the fans allows the sunroof to close over the top of the fan assembly. Currently, rain protection for the fans is provided by another sheet of corrugated plastic clamped to the roof rails. When I’m camped, I clamp this sheet in place over the fans. Once I put solar panels on the roof (I’m currently using a suitcase panel), the front-most panel will shelter the fans from rain.
I use two AC Infinity Airplates that house two 120mm muffin fans each. They are chained together and controlled by an inline Off-Low-Medium-Hi switch. They are very quiet. Low is barely audible. Running them overnight on low has been sufficient to avoid window condensation.
The white corrugated plastic allows light through the sunroof. It acts as a diffuser. I worried I would miss having an unobstructed sunroof, but the suffuse ambience of the filtered light appeals. Enough sunlight gets through to keep me in touch with the circadian march of my surroundings.
A couple USB muffin fans, a sheet of corrugated plastic, and a dowel rod make for a cheap and practical ventilation solution. The only tools needed are a razor and a screwdriver. This can be done even cheaper by buying individual muffin fans instead of the fancy Airplate enclosures.