After starting the humidifier, I used almost 3 gallons the first day! About 1/2 of that was used the 2nd day so it is catching up. I do not run it overnight.
My old 220 receptacle for dryer was like that. Lint and dirt got in there and it fried. I asked WWW to mount the new one I put on to a stud, just be sure it's right side up. Walked by later and it was upside down again Yes he redid it lol.
Essick Aircare EP9800 whole house cabinet humidifier is what we have, along with a small one we run in the bedroom overnight AIRCARE EP9800 Portable Humidifier 3.5gal Espresso Pedestal 43129495241 | eBay
Lint would fall back into the vent if the inlet were in the bottom - which could present a fire hazard. This way, anything that falls off the first screen goes to the bottom of the box, and can be cleaned when the screen is removed. You could mount it sideways if you want. You could probably even just set the box on the floor (it's got plenty of heft to keep it there). Or, one could mount it lower on the wall - I just put it that high up because there are always boxes of stuff beside the dryer and that placement makes sure it isn't blocked and I can reach the screen cleanout better that way. I'm all about utility/functionality. Not like anyone but the pet sitter will ever see it. Not like the dryer doesn't push the air out in plenty of volume/speed. I'd guess it is no worse resistance than when the air is expected to open the louvers on an outside vent.
Here's what we use. 4.75 gal. I use that pitcher to refill. aircare hd3120dcn humidifier - AIRCARE Ultrasonic, Evaporative, & Steam Humidifiers