Hello dear community, I am new miner with 2 small farms now. First farm includes 45 antminer s9 (mixed) and 15 cheetah miner F1 20th.
This farm is divided into 2 parts (cool room and hot room).
Total room size is 7mx3m and a height of 2.5m. The cold and hot sides are separated by an mdf wood with the miners exhaust fan exiting to the hot side. The cool room side size is around 4x3m, has an evaporative cooler the one used in green houses with a size of 2m x 1m (this is my only suction of cool air).

This farm was my first ever built farm. With 30 Antminer s9 as starters everything was fine. When I added the rest, I faced a problem where the hot air exhausted to the hot area is going back to the cold area from the small holes where the miners exhaust fans are inserted.

I tried too many things, tried increasing my exhaust fans to a total of 13,000 cfm but no help. The other fans keeps slowing down their rpm. Tried putting the same fans to suck more air from the evaporative cooler but still some of the fans loose their speed because some of the suction is coming from the inside of the room. I somehow think that my suction opening is smaller than it should be. But I have no choice I can't increase the size of the suction wall (as of what I think).

The same thing happened to me with the second farm which has 45 antminer s9 in a total area of 5mx2.5mx2.4m height which this room was divided into 2 exact areas for the cold and hot room. With an inlet automatic coolers which can supply around 12,000 CFM of air with temperature between 28 to 35 degree Celsius With an exhaust fan of 8000 CFM and another 4200 CFM.

I really hope someone can guide me with what to do to improve these farms cuz a lot of the miners are being affected because of this returned hot air specially with the weather here reaching 45°C ambient temperature.
Or even how to calculate the correct room size /suction/exhaust/etc. For my other coming projects.

Thanks a lot.

I will include some pictures in the coming days to visualize more about the farm.