Window Exhaust Box Concept on Paper
The fan exhaust is a 3-inch diameter pipe which can easily connect to 3-inch foil dryer duct. While this duct could be run to the outside through an open door or window, that would leave an opening that would allow outside air (even the exported contaminated air) to flow freely into the indoor environment where painting is taking place.
Additional materials purchased for the exhaust box were:
1) One 3-inch x 25-foot flexible aluminum foil duct
2) One 3-inch to 4-inch diameter duct increaser
3) One 4-inch diameter louvered exhaust hood (6" x 6")
4) Two 3-inch adjustable metal worm gear clamps
The width of the main window opening is 32 inches. This 32 inch width which fits snugly under the raised window and fits flush against a slightly narrower external opening. This will make it very easy to seal off the outside air from the room interior.
Looking at the hardware components and sill/frame outline, I decided that a height of 12 inches would be appropriate for the design of the Window Exhaust Box.
Rather than free-handing the design drawing like I did for the Paint Booth, I decided to use PowerPoint for the below drawings. These drawings are NOT to scale! Hopefully they are easy to understand:
Drawing 1 - Exterior Window Panel
The 16-inch by 4-inch vent cover is the only piece of hardware that will be attached to this panel. This vent will be cut directly in the center of the panel.
Drawing 2 - Interior Room Panel
Drawing 3 - Exhaust Box Top View
From here the air enters a small chamber that forces the air to exit the window through the 16-inch by 4-inch vent in the exterior window panel.
Drawing 4 - Exhaust Box Side View
For the purpose of these drawings I have indicated a depth of three inches for the connecting chamber between the two panels. The sill dimensions will allow a total depth of seven inches. As I review the proximity of the Louvered Exhaust Hood to the external vent I ma consider some additional depth - perhaps five inches to reduce the velocity of deflected air off the inside of the external window panel.