Is an intake fan necessary for a mining room, or just plenty of exhaust?

[miner417]

Pretty much exactly what the title says. Do you need fan intakes for a dedicated mining room, or just enough exhaust to cycle the air enough, with an open vent to fresh air?

Also for an open air rig setup, I'm having some heat issues already. I have 4 rigs in a single room, hanging on wire racks. Should the cards have fans blowing directly on them as well? The cards are sitting 70-75 at 75-80% fan speed. This was during a major heat wave here, but that was only 90 Fahrenheit temps, which will go up in the summer.

[doktor83]

best is to blow the air OUT of the room, no need to pump in fresh air.

[scambust]

It's about velocity of air. One intake plus one exhaust equals two exhaust.

[ten9]

To minimize the dust inside the room, try to keep positive air pressure. So 2 in 1 out should be ok.

[RentGPU]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

[miner417]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Shouldn't the pressure created from the exhaust, if it's enough, create the suction needed to bring the fresh air in?

[philipma1957]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Shouldn't the pressure created from the exhaust, if it's enough, create the suction needed to bring the fresh air in?

yes

vent  >>>>>>>>  gear >>>>>> exhaust fan >>>>>>

can work  but many details are needed.
4 rigs   could be 6 nvidia 1080 ti cards per rig  or close to 4500 watts
the no fan vent could be too small.
the  fanned exhaust vent needs to be strong
we have two of these
http://www.homedepot.com/p/Master-Flow-1600-CFM-Power-Gable-Mount-Attic-Fan-EGV6/205924917

in the solar array  we have 9kwatts of mixed gear




I put this tarp in today closer to the roof it dropped temps a lot

https://www.amazon.com/gp/product/B000NQ16PE/ref=oh_aui_detailpage_o00_s00?

putting this in next week

https://www.amazon.com/Double-Bubble-Foil-Insulation-125/dp/B017YCYT5S/ref=sr_1_fkmr1_4?


and this is in now
https://www.amazon.com/Car-Insulation-Deadener-Automotive-Lightweight/dp/B016QURU1Y/ref=sr_1_27?




goal is to make a tunnel for wind to flow the heat out the exhaust.

the tarp is on top  it shades  the loft and reflects heat.

the silver bubble is not in yet   it will be second

the car insulation is in and goes around the gear racks fully.  it is a heat shield it is fire proof as it is used on car engines  to reduce sound and stop heat from reaching the driver


      __________________TarP________________
      -------------------------Bubble--------------------
                         @@@car insulation@@@
                         @                               @
                         @ Gear Racks  -.. @
                         @                               @
                         @@@car insulation@@@
___________________loft's floor_________________

3 layers to keep summer heat out. We had heat issues last summer.

we have 2 of these exhaust  on barn wall.

http://www.homedepot.com/p/Master-Flow-1600-CFM-Power-Gable-Mount-Attic-Fan-EGV6/205924917


and we have two of these  to push

http://www.homedepot.com/p/Lasko-Weather-Shield-Select-20-in-3-Speed-Box-Fan-with-Thermostat-B20573/206441059


we may upgrade to this as a push

http://www.homedepot.com/p/Ventamatic-20-in-High-Velocity-Floor-Fan-HVFF-20UPS/202795625


we are at 9 kilowatts

[miner417]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Shouldn't the pressure created from the exhaust, if it's enough, create the suction needed to bring the fresh air in?

yes



vent  >>>>>>>>  gear >>>>>> exhaust fan >>>>>>

can work  but many details are needed.

4 rigs   could be 6 nvidia 1080 ti cards per rig  or close to 4500 watts

the no fan vent could be too small.

the  fanned exhaust vent needs to be strong

we have two of these


http://www.homedepot.com/p/Master-Flow-1600-CFM-Power-Gable-Mount-Attic-Fan-EGV6/205924917

in the solar array  we have 9kwatts of mixed gear

It's currently like this, Exhaust is the in top left of the room. The center of the room is the 4 rigs, mix of rx 470, rx 480, 24 cards total, about 4KW. In the bottom right of the room is the intake vent.

The room is small. 3.5x4.5x8. I know currently the exhaust isn't up to snuff for what I have, I'm looking at probably a 500ish CFM exhaust, or is that lowballing it?  Currently I'm just using a couple small leftover furnace fans to exhaust, and that's probably the biggest issue.

[philipma1957]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Shouldn't the pressure created from the exhaust, if it's enough, create the suction needed to bring the fresh air in?

yes



vent  >>>>>>>>  gear >>>>>> exhaust fan >>>>>>

can work  but many details are needed.

4 rigs   could be 6 nvidia 1080 ti cards per rig  or close to 4500 watts

the no fan vent could be too small.

the  fanned exhaust vent needs to be strong

we have two of these


http://www.homedepot.com/p/Master-Flow-1600-CFM-Power-Gable-Mount-Attic-Fan-EGV6/205924917

in the solar array  we have 9kwatts of mixed gear

It's currently like this, Exhaust is the in top left of the room. The center of the room is the 4 rigs, mix of rx 470, rx 480, 24 cards total, about 4KW. In the bottom right of the room is the intake vent.

The room is small. 3.5x4.5x8. I know currently the exhaust isn't up to snuff for what I have, I'm looking at probably a 500ish CFM exhaust, or is that lowballing it?  Currently I'm just using a couple small leftover furnace fans to exhaust, and that's probably the biggest issue.

yeah way low on exhaust.  my gear is 9kwatts and the two exhaust are  1600+1600 = 3200  which is 5-7 x what you have  .

an we are 2-2.3 x the power    so you need 1000 to 1600 cfm exhaust  not 500 cfm.

how big is your intake vent ?   a 4inch dryer hole? way too small.

these are six inch they would be good for 200cfm so 4 of them would be okay with a 1000cfm exhaust

http://www.homedepot.com/p/6-in-Fresh-Air-Vent-FAV6/100396938?MERCH=REC-_-SearchPLPHorizontal1_rr-_-NA-_-100396938-_-N

[miner417]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Shouldn't the pressure created from the exhaust, if it's enough, create the suction needed to bring the fresh air in?

yes



vent  >>>>>>>>  gear >>>>>> exhaust fan >>>>>>

can work  but many details are needed.

4 rigs   could be 6 nvidia 1080 ti cards per rig  or close to 4500 watts

the no fan vent could be too small.

the  fanned exhaust vent needs to be strong

we have two of these


http://www.homedepot.com/p/Master-Flow-1600-CFM-Power-Gable-Mount-Attic-Fan-EGV6/205924917

in the solar array  we have 9kwatts of mixed gear

It's currently like this, Exhaust is the in top left of the room. The center of the room is the 4 rigs, mix of rx 470, rx 480, 24 cards total, about 4KW. In the bottom right of the room is the intake vent.

The room is small. 3.5x4.5x8. I know currently the exhaust isn't up to snuff for what I have, I'm looking at probably a 500ish CFM exhaust, or is that lowballing it?  Currently I'm just using a couple small leftover furnace fans to exhaust, and that's probably the biggest issue.

yeah way low on exhaust.  my gear is 9kwatts and the two exhaust are  1600+1600 = 3200  which is 5-7 x what you have  .

an we are 2-2.3 x the power    so you need 1000 to 1600 cfm exhaust  not 500 cfm.

how big in you intake vent ?   a 4inch dryer hole? way too small

Shouldn't exhaust have more to deal with the actual cubic feet more than amount of power being used?

Also do you think the heat shield stuff you're using is worth it? Does it seem to be helping?

And final question I think, you have fans that you say are push, are those directed at the cards themselves to blow cooler air directly over them?

[philipma1957]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Shouldn't the pressure created from the exhaust, if it's enough, create the suction needed to bring the fresh air in?

yes



vent  >>>>>>>>  gear >>>>>> exhaust fan >>>>>>

can work  but many details are needed.

4 rigs   could be 6 nvidia 1080 ti cards per rig  or close to 4500 watts

the no fan vent could be too small.

the  fanned exhaust vent needs to be strong

we have two of these


http://www.homedepot.com/p/Master-Flow-1600-CFM-Power-Gable-Mount-Attic-Fan-EGV6/205924917

in the solar array  we have 9kwatts of mixed gear

It's currently like this, Exhaust is the in top left of the room. The center of the room is the 4 rigs, mix of rx 470, rx 480, 24 cards total, about 4KW. In the bottom right of the room is the intake vent.

The room is small. 3.5x4.5x8. I know currently the exhaust isn't up to snuff for what I have, I'm looking at probably a 500ish CFM exhaust, or is that lowballing it?  Currently I'm just using a couple small leftover furnace fans to exhaust, and that's probably the biggest issue.

yeah way low on exhaust.  my gear is 9kwatts and the two exhaust are  1600+1600 = 3200  which is 5-7 x what you have  .

an we are 2-2.3 x the power    so you need 1000 to 1600 cfm exhaust  not 500 cfm.

how big in you intake vent ?   a 4inch dryer hole? way too small

Shouldn't exhaust have more to deal with the actual cubic feet more than amount of power being used?

Also do you think the heat shield stuff you're using is worth it? Does it seem to be helping?

And final question I think, you have fans that you say are push, are those directed at the cards themselves to blow cooler air directly over them?

this is second summer coming.

based on last year 1 1600 cfm exhaust  fan pull and 1 box fan push  was not enough

so we have 2 1600 cfm pull  and it was 95 f yesterday in NJ.  that loft would be 105F  with no gear running.  with the heat shield and the tarp (no photo yet)  running the gear the loft was 92f.

if you look at photos the loft allows heat via the fiber glass roof.   so the heat shield  the tarp and soon the silver bubble warp are needed to prevent sun's heat adding to the gears heat.

plus the  car insulation wrap is made for car engines so it is a fire shield and great lowers the noise.

[doktor83]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Of course it's better to have a push-pull setup if applicable, but if that's not the case it's much better to just push out the hot air, than to pump in fresh HOT air from outside (summer is coming).
Wind is our friend if available

[miner417]

With the way I had to setup the intake, wind isn't really going to help. On those lines, how do you keep water out from your intake? I have a small sheet metal enclosure built at the moment so rain doesn't have a direct shot in, but how do you keep it from blowing in with wind?

[RentGPU]

best is to blow the air OUT of the room, no need to pump in fresh air.

Sorry but thats not true , fresh air must be pumped to cool down the machines , it's a simple rule if there is exhaust there must be intake to fill the hot air pumped out with cool fresh air.

Of course it's better to have a push-pull setup if applicable, but if that's not the case it's much better to just push out the hot air, than to pump in fresh HOT air from outside (summer is coming).
Wind is our friend if available

In summer you can power the intake pump in evening the air outside should be cooler than inside and you can stop it when the sun starts to heat the air outside , i tried this method and the exhaust only method , the one with the intake have a better results

[QuintLeo]

It's about velocity of air. One intake plus one exhaust equals two exhaust.

 one intake + one exhaust = about 1.1 intake OR 1.1 exhaust.

 The ONLY thing having both does is reduce backpressure, which does NOT add significantly to the airflow unless the path between the two is very crowded (like in a S9).


 Running BOTH is a waste when dealing with room-level airflow.


 I've always tried to run intake fans on the EAST side of my place, as that is usually downwind and the rain won't shift directions enough to get to the window as a general rule.
 South is almost as good in most places, but it depends on the prevailing wind direction range where YOU live.

 Second-best option if you have something close to a window (like the neighbor place where I'm at now, or a shed like I had a couple places back) is to run intake on that side, with the "close" stuff breaking the wind.


 I prefer all INTAKE fans so I can filter the air (the rigs might not need it, but I have allergy issues so I *DO*) - but it's not critical if you don't mind the pollen and dust you can use all exhaust instead.

[_javi_]

how do you filter the air?
my main concern about cooling the rigs with no a/c and just forced ventilation is DUST 

[QuintLeo]

Realistically, if you aren't in a major dusty area, dust in mining rigs isn't a major issue - blow them out every month or three.

 My preference for filtered intake positive pressure is more about *ME* having alergy issues and wanting to keep the pollen out, though the reduction in dust in my mining area IS a nice bonus.



 I generally have ended up building up a "plenum" area, commonly 30-36" on a side, then have 3 standard Lasko-type room air fans sucking air in via the plenum through 20"x20" furnace filters. I lose SOME airflow due to the filters, but I'd estimate I'm still getting 4000-5000 CFM flowing through the setup as long as the window I'm pulling the air THROUGH isn't too small.

[stef_stef]

Anyone to help me decide how much exhaust airflow I will need to keep my 4.5 m3 rig room cool? I have a few cards installed there, with a power draw of about 1500W. The cards are running really hot with fans spinning at 90%.

[crypto_alpha]

Anyone to help me decide how much exhaust airflow I will need to keep my 4.5 m3 rig room cool? I have a few cards installed there, with a power draw of about 1500W. The cards are running really hot with fans spinning at 90%.

My idea is to put each rig in a closed rack.
have 2 intakes and have 2 fans blowing directly to the cards.

put 2 exhaust on top of the card  to pull out the hot air out of the rack
try to find 5 inches PVC pipes and guide the hot air out of the room
remember the pipes will get hot ( my record is 70 c )

I'm keeping my rigs cool with this method with cards temp around 48-49 at nights to 55-56 in the mornings

but the noise can and will kill you !

P.S: I prefer the fans to be 5 inches and 110v to lower the load on PSU also try to find high RPM fans with maximum air flow

[stef_stef]

I do not plan on having a closed rig. So far, I'll keep my rigs open, and I need to decide what kind an exhaust fan to get...