Found this in an email and it looks like a good deal for moving air in 6" ductwork so here is the link: http://yescomusa.shop.rakuten.com/p/p/258813291.html?scid=em_20140505_Dedicated&adid=17582 Ray
I used something similar in my fireside kiln this past winter as seen here: http://firewoodhoardersclub.com/forums/index.php?threads/what-is-it-20-questions.2393/ Mine has a limit of 140 degrees F and never got close to that.. Highest it got was 115-120. I'm thinking about replacing it with an 8 inch inline fan to increase the airflow (and velocity in the 6 inch pipe). I think for applications that you're referring to, one could do the same using ductwork to increase the diameter to 8" and then a reducer to go back to 6" Have no idea what the code is for this stuff..
I would like to put some fans similar to this above our doorway to the living room during our remodel.
I used to use one just like that to ventilate a darkroom I had in the basement. I had one of those revolving doors going into it and there was no air turnover. Installed one of those fans and I was amazed at how well it worked.
We put in two of these to move air out of the stove room... Next step will be to tie them to a thermostat so they turn on automatically when the temperature gets to a certain level. I think they are a little more expensive than the inline fan but in my opinion, a little more aesthetically pleasing.. If you go above the doorway you will certainly get slightly warmer air depending on the height of you ceilings..
Ten foot ceilings, going to put a register vent cover in front of it to make it more aesthetically pleasing. Just an on off switch will suffice.
Just thought the price was pretty low and free shipping too.. Dunno how long that deal will stand.. Ray
Upon further review, it doesn't look like quite so good of a deal. Take a look at the pic.... The airflow direction is perpendicular to the duct.... Oh well, back to the drawing board!!!!
This one is an 8" but I use it to move hot air thru the wall from the stove/living room to the bedroom. It works GREAT at keeping the whole (small) house at a more even temperature with the pellet stove. I've even heard of people using ducting with these for longer runs but I think you'd want a more powerful fan for that. On low it keeps everything even and isn't too obtrusive noise wise when going to sleep or hanging out in either room. http://www.amazon.com/Suncourt-TW108-ThruWall-Room-Fan/dp/B004I5H22C
I was gonna say i have seen just what you want on amazon. They mount in wall between rooms and are either round or square with register covers.
I installed mine both ways and it actually worked better to move the warm air into the bedroom where it makes it's way to the bathroom then eventually runs through the hallway into the kitchen where the tstat is. Maybe my situation is rare but I tested it with a thermometer and how long it took to warm up etc. lol I'm such a nerd sometimes