We have them running around 60F with continuous fresh air, exhausting hot air outside. Humidity is about 40%

I am only telling of my experiences, I have quite a few 3 ph 200 amp clusters, the average wattage is about 1100 watts.

We are running them at colder temperatures at higher voltages, the bitmain power supplies are very temperamental to voltage. If you run one at 120 volts you will be pulling 1400 watts, which is not a good idea. The power supplies get more efficient at higher voltages, and the fans work less when its colder.

Do you have outside doors, you can replace solid doors with metal bar'd doors. The problem you have is your pumping energy into the room, you have to remove the heat. You really have to vent the exhaust heat outside somehow, sounds like your over 105 degrees in the warehouse, which means you may already be looking at damage to the equipment already.

I do believe you really have to get rid of the hot air, I have a few 100 of these running and there is really no way treat the hot air coming out of these units, you just have to duct it outside.

Calculations are simple 400 amp x 208 volts x sqrt(3) gives you 144,102 watts of power, at 80% thats 115,281 watts. Our farm the s9's are averaging about 1100 watts each, which would give you 104 s9 miners. The real trick is balancing the load, we have multiple racks of 200 amp services and have yet to balance one perfectly, leg C is always about 15% less then A or B. Also, use larger wire size, when you have a large feed you have to watch for voltage drop, that will cause the miners to draw more power and start popping breakers.

You have to get rid of the hot air, and bring in fresh air. S9's generate 90 cfm of air flow each, if you can capture the hot air you can channel it to an exit point. Dont try and cool the room with an air conditioner, its better to use that power for miners. Evaporative cooling works, but it raises the humidity and can cause corrosion, although s9's may only be viable for another 5 to 8 months. If you have a ceiling vent you might try arranging in a circle and vent the air up, that takes advantage of hot air displacement, I have seen a number of large setups do that.

just my $.02

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