Cooling home mining farm, looking for advice

[Darnn]

Hello everyone.

I am setting up small farm up in my attic. Farm consistst so far from 3 Antminers S9 13.5TH and 7 Antminerse L3+. I have done few tests runs, and so far my main concern is temperature. I have made fairly small room around the stairs, 2x3 meters maybe and it'se heating up very fast. With 1 L3 and 3 S9's running room was going to +35 and S9's were shutting down. I made cutouts in walls and led termic pipes outside with hot air but it didn't solve the issue completelly. Fan I had set up as inlet from outside of building is nowhere near enough to provide enough cold air from outside. I am looking now to buy much more efficient fan for intake, but the question is, how much CFM I need? I read from many sources that single antminer S9 has around 210-230 CFM. I could not find any reliable information about l3+ but even if it's around the same (I think it's less than that) I need around 2300 CFM fan blowing air into the space.

Now the question is how much could air I should blow into the room. I was thinking about overkilling it a bit so in future I can increase the amount of machines. I am looking at 7960 m3/h fan which is around 4685 CFM. Is it too much? the fan is supposed to draw around 250 W but I think without it running all 10 miners would be impossible outside of winter ( middle east europe).

PS. Yes I know setting up mining operation in house is not efficient and problematic but I had no other place .

[fanatic26]

You are making a classic mistake. You need to remove heat, not add fresh air. All the intakes in the world will do nothing if you dont get rid of the heat. What you want is active exhaust and a passive intake. The miners will pul lthe air in themselves if you do it properly. There are many guides and ideas on this site that will help you.

[Darnn]

well this is how I set up the exhaust

https://imgur.com/a/1lN8nhu

[ReadyPlayer1]

You are making a classic mistake. You need to remove heat, not add fresh air. All the intakes in the world will do nothing if you dont get rid of the heat. What you want is active exhaust and a passive intake. The miners will pul lthe air in themselves if you do it properly. There are many guides and ideas on this site that will help you.

Fanatic, with respect you need to add any air you take out. Otherwise you’ll destroy your home with negativite pressure. I have over 27 miners and I have 6,000 cfms going in and out of my room in my home. Cheap gable fans work best. Keep costs low and make it simple. Most of my chip temps get into the the mid 80s when it’s 80+ degrees out. So I think your setup should be fine if you can get 4,000 cfms in and out. Check my previous post and look at my images.

[OgNasty]

well this is how I set up the exhaust

This is nice.  Might want to slap some duct tape around those exhaust lines and the fans to keep the hot air from leaking back in the room.

[Darnn]

Okay thank you for tips, I was thinking of taping inlets to fan aswell, because the middle miner was getting consistently to 80 C and shutting down, I guess too much hot air was just going around the pipe. On a side note - is it worth also to direct the outlet of power supply into the pipe for hot air or it's rather marginal in compare to heat output of antminer?