mlts22 wrote:
One idea I plan to do is see about a roof cover, but add a filter, then run the fan backwards (so it sucks air in, rather than blowing it out.) This would create a nice positive pressure to keep dust out.
We run the Fantastic roof vent fan reversed on it's "IN" setting all the time when traveling off-pavement in our Class C in order to keep the dust down inside. No filter is needed because the roof vent fan pickup is of course way up high in relatively clean air, while all the dust is being picked up and kicked up down low by the tires. Not a lot of air "flow" actually occurs anyway, as all the fan is doing is trying to bring air in but can't because we have all other openings in the RV - including the dash A/C turned onto circulate only - closed except for the flapper vent for the cooktop exhaust fan. All the roof vent fan is doing is maintaining constant air pressure inside the coach so no dust can come in down low from the tires through any (hopefully, very few) tiny cracks in the coach walls or flooring.
This has worked great for us ... especially out on desert roads.
