Your big concern with the setup, I think is that you want to have an in and out fan beside each other,
Your best bet will be to pipe in the outside air to the back side of the room.
You could likely run 2 5" dryer liners in over and down the back wall, and get away with a large exhaust fan.
As for the CFM you are after, you will never get a silent version. That's going to be hella noisy lol
Yes let me just explain to my landlord why i want to take down a wall from his apartment so i can have two windows
![Tongue](https://bitcointalk.org/Smileys/default/tongue.gif)
And i never said silent, two box fan at full speed arent silent at all and the CFM is plenty, they just dont have enough pressure so a bit of wind and BAM they basically stop their spin. A metal equivalent with more angled blade would be quieter, but much more performant!
I'm sorry did I say take down a wall???
If you are going to be rude, read the fucking comment.
I said pipe the fan for intake an exhaust to different parts of the room.
That's a matter of running a line, not using a second window.
I also stated use a furnace fan, but I see you thank someone else for that.
I'm done helping.
Good luck
There is no need for that. And Bye.
What are the dimensions of the room (LxWxH) and dimensions of the windows and quantity?
There's a lot of HVAC calculators out there for air exchange CFM requirements, if you want to do it right this is how you do it.
Having a pile of miners running with the air just blowing willy-nilly in the room is going to create hot and cold spots, you want to read up on fluid dynamics, turbulence, what causes dead zones, and visualize the airflow in the room.
Put the big furnace style blower as an exhaust fan in one window and an array of cheap box fans to keep the air moving from the inlet window, if you can create a wind tunnel effect across the miners you will be better off, but I don't know the layout of the room and what we're working with here.
Draw it up or post pics or both.
Well i think its overcomplicating it, since 2 box fans are doing the job. But have too low pressure to keep the air going when the wind hit them or if i add a filter to catch the snow.
But i'll add some details at the end of this post.
![Smiley](https://bitcointalk.org/Smileys/default/smiley.gif)
Thats an interesting idea. The blower type fan i saw were extremely loud, i wonder if i could build an array of them (slower/quieter ones) and pipe the exhaust to a wooden frame that would hold the exhaust in the window.
Way too expensive setup for my usage but maybe for my next place. Hrm. Definitively noted.
Virosa this is a good idea. I was looking into larger industrial exhaust fans like this:
http://www.princessauto.com/en/detail/18-in-single-speed-ventilating-fan/A-p0772343e;jsessionid=YjEYeEHB2F0F3ZtnGxZTpI37.pal-prod-com1 for myself, but it would probably be too loud for your application.
Actual furnace fans aren't that loud, or they wouldn't be tolerated in homes. Why don't you try to find a trashed furnace and salvage the fan out of it to see how it does? It can't be worse than the plastic box fans, and can be ducted way easier.
No idea where to find that, its illegal to loot scrapyards here. They're fenced and shit.
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The window opening is 16inches by 48~ inches.
The room is small, like 3x3x2.5meters.
Red is hot spots, circles is because there are portable rigs sorta spread out, but not really like in the pic. Yellow arrow is box fan airflow. The red line is a rack, 80% of the heat come from there. And top right is the window, the top box fan push heat out and the bottom one pull cold air in.
I'm pretty sure the metal 20" box fan will be good enough replacement for the intake fan + a filter to prevent snow from snowing on my rigs.