Pressurize a camper


if you are introducing vast quantities of air into the cabin , ie through a powerful fan, you would need a good filter medium that would probably need cleaning or replacing several times a day in really dusty conditions.



if you are introducing vast quantities of air into the cabin , ie through a powerful fan, you would need a good filter medium that would probably need cleaning or replacing several times a day in really dusty conditions.

Not necessarily. If the air intake is up high you get less dust. Tis why most air intakes for this purpose are top face of camper or even roof of camper. Air is less dusty higher up you go.


Establishing and maintaining a small amount of pressure on the inside of most RV's - whether towed or self powered - need not be rocket science.

We have a good old Winnebago built Itasca 24 foot Class C motorhome based on an overkill E450 chassis that we occasionally take off-highway in the Western U.S. on dusty dirt/gravel roads looking for rocks.

We travel with the Ford's dash air flow set to "Max A/C" which recirculates all interior air whether heating or cooling. (This control is actually labeled in a confusing manner because when set to Max "A/C" you can actually set another control to have the air heated or the air cooled while being recirculated.)

We then close up all coach windows and roof vents except one - the vent in the roof at the front with a multi-speed powered, reversible fan in it. When traveling, we set this fan to blow IN on it's lowest fan setting. However, no outside air can actually be brought in because everything is closed up - including the cab air system when set to it's Max A/C recirculate mode.

What the roof vent fan does is establish and maintain a small amount of air pressure within the entire coach and cab interiors of our motorized RV.

This makes it impossible for any dust to enter anywhere through any crack or other opening. It works like a champ for us.

This procedure also keeps out all built-in generator fumes when camped and running our roof air conditioner in scorching desert heat.
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Having done several decent trips outback here in Oz, this subject was one of the things higher on the list to address/build in to our overland body. I plan to use 2 of these 'snorkel heads' mounted at of the front of the body on the front left and front right upper corners. They'll be removable and have blanks for when not on dirt. Each one will feed a forklift or tractor air cleaner housing with a big paper element in each that can be removed and cleaned. With 2 x 3" (75mm) holes force feeding filtered air into the cabin there'll be no way bull dust will get in. I then plan to have two slightly smaller 2.5" (63mm) vent holes leading from the interior to the under bed back locker, and then two slightly smaller 2" (50mm) floor mounted exit vents at the base of the lockers.. My theory being that if each 'area departure vent' is slightly smaller than the supply vent, then each compartment will have a certain amount of pressure build up keeping the dust out. The only thing I'll have to be mindful of is that the shower and sink plugs are in when on the road, and the lid on the composting toilet has a good seal. It's advisable to have floor vents anyway in case of gas leakage etc.. Mine will just vent into the under bed lockers... image.jpg


I just picked up an used Arctic Fox travel trailer that has a Fantastic Fan knock-off in one of the crank up roof vents. First trip out was about a 45 minute drive down one of the dustiest roads I’ve ever driven on, before I started on the dirt road I closed all vents and windows except the vent with the fan. I turned the fan on mid speed with the air blowing into the trailer and when I arrived at the campsite there was zero dust anywhere inside the camper.
I wasn’t convinced it was just the fan keeping the dust out so on the way back down the same road I did the same with all the vents and windows but didn’t turn the fan on.
Good god, when I reached the end of the road it looked like I had just driven across the desert, I couldn’t believe how dusty it was inside. Now I admit I forgot to close the vent over the fan so it may have been a bit better but going forward, anytime a dusty road is involved, the fan will be running.
this might be someone's next great invention:

remember the bottle generators for your bicycle headlight? it had a knurled wheel which could be flipped against the tire sidewall to make juice. why not a similar gadget for a trailer fan? when the tires were revolving, fan speed would be governed x rpms. not many parts to break or be serviced - all mechanical.
Except the metal tread on the shaft against the tire is rotating about 2500+ rpm and bike tire at best runs about 200, the side walls of your trailer tire, in time, will blow.


Gentleman Adventurer

@mep1811 how did this work out for you? I am toying with design ideas for a filtered, pressurized air system for dust control. Any feedback or lessons-learned from your project would be appreciated.
It seemed to work well. I never really tested before and after. What I thought would be more dusty was less.


Part time fulltimer
I used to turn the roof Maxxfan on 100% in when we hit the dusty dusty, it did help

But it's quite a battle with a standard RV quality rear-door camper, I said the next one would be side entry.

Do like the designs (from down under?) where there is a rear door but it's double sealed with a gasketed set of stairs that cover the door in transit and then flip down for use

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