Farm Design , Suggestions Needed.

[mikeywith]

I am planning to set up a new farm and I am facing some issues regarding the best cooling set up.



Sorry about the mess, I am not really good in sketching

So the room is 12*6 Meters (40f*20f) , and I am going to split the hot and cold sides of the room, 40 S9s will be in this farm , so I am going to have a total of 4 large fans 70cm*70cm  , each fan does 3000cfm ( please ignore the number of fans in the image), I will place two for intake and two for exhaust.

I am also planning to place the exhaust side of the miners only 1 meter (3.2f) far from the wall , leaving 5 meters (16f) for the cold side of the room, I think if I do this, the hot air will be able to leave the room faster.

Now I have a few concerns and they all come from the lack of proper understanding about the cooling system, in my previous set-ups , I counter all heat issues by adding air-condition/s to the cold side of the room, but this time I plan to save some power so I can fit more miners in there, but without air-cons I get a bit worried about cooling, thus I have these 4 questions/concerns.

1- are 4*3000cfm fans (2 intake and 2 exhaust) good enough to cool 40 S9s running in normal mode , keep in mind temps in the summer can get to as high as 40c (104f).

2- is the distance between the miner exhaust fans and the wall enough ? is it too much/little?

3-is it better to have only fans to exhaust the air, or add shutters to the wall ?



4-at what height should I place the exhaust fans, should I place them on top because science say hot air rises? or place them in miner's levels so that hot air get's blown directly blown at those fans.

I have also came across this design https://www.youtube.com/watch?v=775gzE7qCVw&t=201s, is it any better than the old split design?

any suggestions , tips will be highly appreciated.

[1713574954]

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[1713574954]

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[1713574954]

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[philipma1957]

6000 cfm in 6000 cfm out

40 x 220 = 8800 cfm are the pull of 40 s9 fans.

My guess is you need more 1 or 2 more exhaust fans.

And two or 3 filtered fanless vents.  Use a washable air filter. Say 50 by 63 cm these cost no power

You can go low with them on the cool side

Cool air outside

Vvvvvvvvvvvv
Vvvvvvvvvvvv

Vent______fan______vent ______fan______vent

[mikeywith]

6000 cfm in 6000 cfm out

40 x 220 = 8800 cfm are the pull of 40 s9 fans.

My guess is you need more 1 or 2 more exhaust fans.

Phill, does an S9 really need 220cfm for exhaust? also won't the vents in hot side wall help get rid of that hot air? I am trying to keep the set-up as cheap as possible, adding another fan is doable, adding 2 more is a bit too much, but if need be, I got no other option.

And two or 3 filtered fanless vents.  Use a washable air filter. Say 50 by 63 cm these cost no power

not sure how it didn't come to mind, I could add more than 3 for that matter, any disadvantages with having vents on the intake side?

Vvvvvvvvvvvv
Vvvvvvvvvvvv

sorry I don't get this prat !

Vent______fan______vent ______fan______vent

What about

Vent-----------vent------------vent------------
-------- fan-------------fan----------------------

vents' row : 50 cm from ceiling
fans' row : 100cm from ceiling

no?

[philipma1957]

Vvvvvv
Vvvvvv.   Air flow    From outside into intake.

Try your intake pattern.

220 cfm is max and conservative .   The intake vents with only 2 fans will be good.

Maybe three fans on exhaust.   The fans go from 4 to 5.  Which is not much extra power.

[mikeywith]

ok sounds great ,  I will go with 3*3000cfm fans on the exhaust side plus 7 vents , each will be 70cm*70cm , and for the intake I will go with 3*70cm*70cm vents and 2*3000cfm fans and will try this set up

intake :

Vent--------Vent----------Vent
------- Fan -----------Fan--------

exhaust

------- vent--------vent----------vent---------
Vent---Fan--vent---fan---vent---fan--vent---

any recommendation about how high/low to place the fans and the vents? the building is about 4 meters (13F) in height, I want to avoid the first meter from ground so the fans don't end up sucking all the dust outside.

I am still worried about this

2- is the distance between the miner exhaust fans and the wall enough ? is it too much/little?

[philipma1957]

3 exhaust fans  should be  9 - 11 feet  they do not need to be at top of  room

3 passive intake fans need to be at least 1 foot off ground

intake vent 1 foot off ground

how tall are miners ?  and are they 1 shelf high? or 2 shelves  or 3 or 4?

do you plan on a no move hot cold isle?

[mikeywith]

how tall are miners ?  and are they 1 shelf high? or 2 shelves  or 3 or 4?

There are no miners there yet, I can place them how I want  , I am thinking 4 rows , 10 miners each

thinking about leaving 3 feet from ground, than place the first row , each row will be 1.64 feet , so here is how it should look

Roof
3.44 feet space
row>  10 miners
row>  10 miners
row>  10 miners
row > 10 miners
3 feet space
Ground

shelf width will be kept short enough to face the exhaust fans

since I have this set-up for exaust

------- vent--------vent----------vent---------
Vent---Fan--vent---fan---vent---fan--vent---

each vent is 2.2f and so are the fans but distance from first to last fan =  2.2*5 = 11 feet so out of 40 feet in total  I will only utilize 11 feet , so here is how it look

------- vent--------vent----------vent---------
Vent---Fan--vent---fan---vent---fan--vent---
-------  2*s9-2*s9-2*s9-2*s9-2*s9-----------

[Artemis3]

------- vent--------vent----------vent---------
Vent---Fan--vent---fan---vent---fan--vent---

These two walls... I'm pretty sure some of the hot air will run circles which in turn is like creating pressure against the exhaust of the miners.

Unless your inner wall had no vents and only fans...

How is the humidity over there?

[mikeywith]

These two walls... I'm pretty sure some of the hot air will run circles which in turn is like creating pressure against the exhaust of the miners.

Unless your inner wall had no vents and only fans...

That set up is for the exhaust side ,  ok let me explain the set-up a little bit clearer.

intake :

Vent--------Vent----------Vent
------- Fan -----------Fan--------

-wall-------------------------------------------wall-
                                                                  -
exhaust                                                    -
                                                             -
------- vent--------vent----------vent---------   -
Vent---Fan--vent---fan---vent---fan--vent---  -

The two sides will be 100% isolated, I will be using MDF panels , and use a cnc router to make squares for the exhaust fan of the miners, so how does explain the " run circles" ? I don't get it, because if the two rooms are isolated, and the fans push the air from cold to hot side, how is it possible for the air to run circles?

How is the humidity over there?

Very low , it's located somewhere in the mountains , it's very dry there so there should be no problem as for as humidity is concerned.

[graymatter]

Take into consideration the airflow reduction in any filter medium you use.  Also consider how much filter surface area you need in order to accommodate your CFM rate.

Pocket filters are best for high airflow environments.  Most air filters will state in fpm.

Example from Google:
Select air filter dimensions (length, width, thickness). 2. Calculate airflow velocity in linear ft./min. using air volume rating of fan in cfm divided by surface area of air filter in sq. ft. (i.e. 200 cfm./0.50 sq. ft. = 400 fpm)

If your CFM is higher than the capacity of the filters they will loose efficiency and essentially stop filtering.  The more the discrepancy the more they don't work.

Most people vastly underestimate how much filter surface area they need for a bitcoin mine.

Also consider the added resistance the filters add when considering fan size / quantity.

[Artemis3]

[...]

So then you just need it above 20% to prevent static build up, good to know.

Yes it runs circles inside the hot room, thus creating pressure against the (asic miner) fans. This is what i meant with my post. To understand "pressure", just put some obstacle near the exhaust fan of one unit, such as your hands, and watch the temps.

In my opinion, there should be only fans in the inner wall (no vents), and the outer wall better have lots of vents (or big enough) so the air can go easily.

And yes I'm only referring to the exhaust part. Intake is probably fine. Funny you didn't just mirror that, a vent is not a cheaper fan, it lets some air go in the opposite direction...

Oh and BTW, this hot room try to make it walk-able, you'll find it very useful for some unrelated things later. Think, giant clothes dryer Just don't abuse it and create unwanted pressure lol.

[mikeywith]

I am a bit confused now, which one is correct ? This ?

Yes it runs circles inside the hot room, thus creating pressure against the (asic miner) fans.

or This?

... and the outer wall better have lots of vents (or big enough) so the air can go easily.

What inner wall are you talking about exactly ? I think there is a bit of misunderstanding, here , there is no wall/vents in the inner wall, I think you didn't quite get the idea, or maybe I am too stupid to understand the logic , basically I have 3 walls.

Intake Wall ( Fans and Vents)
Partition Wall (splits the miner's fans , intake fan is in the cold/intake side and exhaust fans are in the hot/exhaust part.
Exhaust Wall (Fans and Vents)

the middle/partition wall is something like this

Intake side



Exhaust side



I hope you didn't think that I am going to put vents in that wall , this will make the whole idea of isolating the room pretty useless, please refer to this topic to understand the set-up a bit clearer.

Oh and BTW, this hot room try to make it walk-able, you'll find it very useful for some unrelated things later. Think, giant clothes dryer Just don't abuse it and create unwanted pressure lol.

1 meter should be more than enough I guess, that is 3.28F , should be more than good for clothes dryer  

Thanks a lot for the all suggestions.

Take into consideration the airflow reduction in any filter medium you use.  Also consider how much filter surface area you need in order to accommodate your CFM rate.

Yes the extra vents on the intake side should account for any filtration surface.

[Artemis3]

Then i guess its my mistake interpreting the ascii art. If its just 3 walls then all is fine. I understand the middle wall perfectly, but the art made it look like there were two walls before and after that, so it doesn't matter then.

Some heat re-flow can actually be useful to reduce humidity, but that's not your case here.

[altair_tech]

I compiled a lot of information that was floating on the interwebs, along with my own engineering and design experience to draft a comprehensive guide on bitcoin mining farm design.
Part 1 is focused on airflow handling. It also includes a handy calculator for sizing exhaust and intake area.

https://altairtech.io/designing-a-bitcoin-mining-facility-airflow-management/

Comments and feedback are welcome.