Picked up a brand new (second hand) attic fan with thermostat to use on the top of my generator enclosure.
Fan moves 1200 CFM. This should be more than enough to keep the generator cool and prevent fire. In my view it will even air cool it better than it standing on its own. Well at least i hope.
So now i got this fan on the top of a large box. Approx 4' x4' at the base and around 3' high.
Sides will be enclosed tight with layer of insulation as if it was an R4 wall ie 2x4 stud bay with insulation.
Floor is a plastic pallet i got free. I could one day regret using this but for the moment i am in love with the pallet. Think future when it goes to ground level i have automatic rot free base that is raised off the ground by 6 inches.
Roof will be another pallet. Before you ask no plans this is flying by the seat of the pants. Dont have time to do drawings at this stage. Got to wing it Xmas is around the corner.
So now comes issue of air intake. Exhaust fan is 14.5 inches in diameter so i figure given this is going to be a tight box i gotta put some intake vent on it and want air intake starting at the bottom and distributed around so all sides of generator get cooling and air flow.
By my calc PXR squared says area of exhaust vent is 165 square inches.
I am thinking if i run a strip of soffit vent around the sides on all four sides including the door I should be ok to have matching air intake and most important not have bugs and critters get in.
Soffit vent best i can tell is 2.75 inch wide but looking at the pic i say at best 40% perforation. So i figure for each 2.75 the effective open area is 1.1 inch. If sides are 4' x4' square that says i got 212 inchs of opening.
Should be quiet a rush of air passing through those vents when the fan gets going.
Just wondering if sofit vent will collapse or not if its supported all along its lengths and secured with staples. Think here of two pieces of 2x4 laying horizontal and strip of soffit vent secured between them along the edge.
Questions do you think it will hold ?
Do you think this would work and be enough intake ?
Dont want a place where the likes of insects would find their way in and set up home and dont want to have to clean filters all the time. Soffit vent holes are kinda self cleaning in a way given they are pressed in. I could simply hose down from time to time.
Also trying not to make too large of an opening that lets all the noise out.
Any comments critiques or additional ideas welcome.
Alternatives i have thought of using are floor registers, Houshold air intake vents for ventilation systems , vent covers for washroom exhaust fans when mounted on walls.
Most are designed with view to exhaust and close to keep insects out or assume non insect environment like interior stuff.
Also looking for vent to be weather bearing.
Thanks for any input.