30kW mining farm - need ventilation advice [Reward]

[brokenarrow2]

Hi, I'm helping someone build a smaller mining farm and the capacity for the electricity will be 30kW.

According to this video by Block Operations https://www.youtube.com/watch?v=D7e-bKDFidk for each miner we need 200 cfm of airflow, which is equal to 340 m3/h and a total of 4000 cfm. To start with, does that make sense if a rig produces around 1500w? For this we would have 20 rigs.

Here's an drawing of what it will look like:
https://imgur.com/qMnrqS8.png

Here's the plan:
- 4-6 shelves (The pink boxes in the image).
- 3-4 rigs on each shelf
- Air intake on the floor, which basically is a raised floor, with a 20x50 cm (8x20") hole that blows air from an intake. Each vent will be 0.1m2.
- Each rig will be 8xGPU, about 80cm wide, with 7 Delta fans (0.8A, 113 CFM) on each, blowing a total of 791 CFM air per rig into the middle of the room.
- Intake fan is 500mm (20"), pushing 5800 cfm at max, taking air from outside with a dust filter
- Exhaust fan is 500mm (20"), pushing 5800 cfm at max
- The fans can be regulated according to the outside temperature

So the flow is cool air from outside, to each rig, out into the room, and out of the room.

At the end of the room (top in the drawing) will be an exhaust fan, moving the air out of the room, and to the outside, through the roof or front of the building.

So the questions are:
1) Will the air from the floor vents be equally distributed so all rigs get cool air? Or is there any better option? Would a continuous vent along wall like 300x20cm (120x8") be better?

2) What's the best location for the exhaust fan, to make sure all rigs are cooled equally. Now that I think of it, centered in the room might be better. Or would two fans be better?

3) Would it be better to just have an intake fan in the bottom of the room (where it says 3.4) and make a wind tunnel through the room? Where would the rig fans get their air from in that case? Some kind of turbulence?

4) With 500mm (20") vents connected to the fans, the area of the vent is 0.2m2, so I'm considering if this should be equal to the floor vents, but I'm not sure.

5) Is 200 cfm per rig adequate and would each fan need to move 2000 cfm each? Which means I basically can triple the power consumption and still move the hot air out if the fans are on max?

6) Does the size of the room matter? Would it be better to have it less wide?

I'm looking forward to hear your thoughts on this. If you have a lot of experience in building farms with direct air cooling, and can consult me on this by email, PM me and we can discuss a reward.

Thanks!

[1715695922]

1715695922

[1715695922]

1715695922

[STATIK]

Hi, I'm helping someone build a smaller mining farm and the capacity for the electricity will be 30kW.

According to this video by Block Operations https://www.youtube.com/watch?v=D7e-bKDFidk for each miner we need 200 cfm of airflow, which is equal to 340 m3/h and a total of 4000 cfm. To start with, does that make sense if a rig produces around 1500w? For this we would have 20 rigs.

Here's an drawing of what it will look like:


Here's the plan:
- 4-6 shelves (The pink boxes in the image).
- 3-4 rigs on each shelf
- Air intake on the floor, which basically is a raised floor, with a 20x50 cm (8x20") hole that blows air from an intake. Each vent will be 0.1m2.
- Each rig will be 8xGPU, about 80cm wide, with 7 Delta fans (0.8A, 113 CFM) on each, blowing a total of 791 CFM air per rig into the middle of the room.
- Intake fan is 500mm (20"), pushing 5800 cfm at max, taking air from outside with a dust filter
- Exhaust fan is 500mm (20"), pushing 5800 cfm at max
- The fans can be regulated according to the outside temperature

So the flow is cool air from outside, to each rig, out into the room, and out of the room.

At the end of the room (top in the drawing) will be an exhaust fan, moving the air out of the room, and to the outside, through the roof or front of the building.

So the questions are:
1) Will the air from the floor vents be equally distributed so all rigs get cool air? Or is there any better option? Would a continuous vent along wall like 300x20cm (120x8") be better?

2) What's the best location for the exhaust fan, to make sure all rigs are cooled equally. Now that I think of it, centered in the room might be better. Or would two fans be better?

3) Would it be better to just have an intake fan in the bottom of the room (where it says 3.4) and make a wind tunnel through the room? Where would the rig fans get their air from in that case? Some kind of turbulence?

4) With 500mm (20") vents connected to the fans, the area of the vent is 0.2m2, so I'm considering if this should be equal to the floor vents, but I'm not sure.

5) Is 200 cfm per rig adequate and would each fan need to move 2000 cfm each? Which means I basically can triple the power consumption and still move the hot air out if the fans are on max?

6) Does the size of the room matter? Would it be better to have it less wide?

I'm looking forward to hear your thoughts on this. If you have a lot of experience in building farms with direct air cooling, and can consult me on this by email, PM me and we can discuss a reward.

Thanks!

If you are going to invest into 20 miners why not hire a professional to calculate this out? Humidity can cost you a lot more...

[brokenarrow2]

I did, both with an HVAC firm, and a Ventilation (?) firm, but none seem to have experience with getting rid of 30kW of heat from a rather small room.

The ventilation guy told me to contact the HVAC which then recommended to put 2 x 14kW AC units, to keep the room at 16C which is probably to cold, and insane power cost. I believe the extra unit is for backup, in case the first fails, but even 14kW sounds too much.

Then I got back to the ventilation guy, and proposed to have a solution with 2 x 500mm fans, and he was unsure if it was going to work at all, but they can build it for me. So I ended up here to get some more feedback...

The relative humidity here is 60-80 around the year, and I'd be happy to get insights into how that should be handled. Should the air on the intake ge dehumidified? I don't see anything like that on the big farms which have something like 1200 mm intake fans, but maybe they are located in dryer climate?

Thank you in advance!

[SGMPhil]

Just a thought, but have you considered just leasing some space in a data center? They handle all of the power and environmental issues for you and would keep you from having to worry about any of this

[eissug]

Make sure you call the power company and tell them what you are doing.  Give them the steady state load and total demand.  The transformer might be undersized for what you want.  They will probably replace it for free if it isn't, but if you burn it up they will probably want you to pay for it.  It might take them 2-3 replacements before both parties figure out what happened.  I was lucky and got a call before things scaled up.  

You are somewhat lucky with that humidity.    Miners have dried me out.  I'm at 8% RH with the things going.  Dumping 72 gallons of water per day into the air gets me to about 30%.  

I'm not sure about the HVAC numbers.  You should need around 9 tons and that should only consume around 1.2kw per ton.  It sounds like they were listing the heat capacity of the AC unit in KW rather than the power consumption.

I would probably size the AC system for an ambient temperature of 75-80 in the room.  You could probably get by with fewer tons.  You'll want it to run non-stop I think???

Disclaimer:  AC for me was an intellectual exercise.  Never had the pleasure of needing it and none of my vehicles have it.  

[brokenarrow2]

@SGMPhil: I considered data centers, but what I could find nearby was only for rack mounted servers, and probably not a machine using 1500 watts. Haven't asked though, but I suspect it would be more expensive than renting a warehouse... thanks for the idea though.

@eissug: Sure, I think whoever rents out the warehouse is in charge of that, if you ask them what power you need, but good point, don't wanna break anything..

[eissug]

They might be responsible if the bill is in their name.  I imagine it will be in yours.    I was pretty surprised to find out all of the rules of my power company!  Mining is not an activity that the power grid was designed for.  The power company did not size their distribution network to give everyone 200A who has "200A" service...

Also, I was thinking about it and it would probably cost less to AC the room than dehumidify.  Maybe it would only be close, but AC gives you control.  Depending on the warehouse it might make sense to insulate the walls a little more too.

[Sandal_Hat]

Hi, I'm helping someone build a smaller mining farm and the capacity for the electricity will be 30kW.

According to this video by Block Operations https://www.youtube.com/watch?v=D7e-bKDFidk for each miner we need 200 cfm of airflow, which is equal to 340 m3/h and a total of 4000 cfm. To start with, does that make sense if a rig produces around 1500w? For this we would have 20 rigs.

Here's an drawing of what it will look like:


Here's the plan:
- 4-6 shelves (The pink boxes in the image).
- 3-4 rigs on each shelf
- Air intake on the floor, which basically is a raised floor, with a 20x50 cm (8x20") hole that blows air from an intake. Each vent will be 0.1m2.
- Each rig will be 8xGPU, about 80cm wide, with 7 Delta fans (0.8A, 113 CFM) on each, blowing a total of 791 CFM air per rig into the middle of the room.
- Intake fan is 500mm (20"), pushing 5800 cfm at max, taking air from outside with a dust filter
- Exhaust fan is 500mm (20"), pushing 5800 cfm at max
- The fans can be regulated according to the outside temperature

So the flow is cool air from outside, to each rig, out into the room, and out of the room.

At the end of the room (top in the drawing) will be an exhaust fan, moving the air out of the room, and to the outside, through the roof or front of the building.

So the questions are:
1) Will the air from the floor vents be equally distributed so all rigs get cool air? Or is there any better option? Would a continuous vent along wall like 300x20cm (120x8") be better?

2) What's the best location for the exhaust fan, to make sure all rigs are cooled equally. Now that I think of it, centered in the room might be better. Or would two fans be better?

3) Would it be better to just have an intake fan in the bottom of the room (where it says 3.4) and make a wind tunnel through the room? Where would the rig fans get their air from in that case? Some kind of turbulence?

4) With 500mm (20") vents connected to the fans, the area of the vent is 0.2m2, so I'm considering if this should be equal to the floor vents, but I'm not sure.

5) Is 200 cfm per rig adequate and would each fan need to move 2000 cfm each? Which means I basically can triple the power consumption and still move the hot air out if the fans are on max?

6) Does the size of the room matter? Would it be better to have it less wide?

I'm looking forward to hear your thoughts on this. If you have a lot of experience in building farms with direct air cooling, and can consult me on this by email, PM me and we can discuss a reward.

Thanks!

I did mine with around 20kw. I am not sure what i am looking at exactly in your drawing.

I hope u realize that the sound will be VERY LOUD. U can hear it even 15-20 meters away.


Tips:
Shelves - use good shelves shelves that can take over 100kg, not those ikea shelves with 32-40kg max load weight.
Your air intake and exhaust - MAKE SURE the exhaust HOT air does not recirculate into the AIR INTAKE in any situation. Meaning the hot air that goes out does not get to back into the intake if the wind blows a certain way. Account for the fact that wind changes and put a good margin of safety on this.

Airflow - U dont need air intake. As long as the room is sealed and air is pushed outside the room, air will automatically enter the room through any opening. The amount it pushes air out depends on the pascal air pressure in the room. Mine is around 200 pascal via box fan, something like page 280 here http://rosenberg.com.sg/wp-content/uploads/2015/04/worldoffans_en-2.pdf . U can use any sort of fan though. In general, dont take air in from ground as the air is abit more dusty and since warm air rises, it is abit better to put air out-take/exhaust fan at higher point or at least middle.
Also six 0.1m2 holes is about 0.6m2 total. That may be too much. Your air pressure pascal might be too low. U may wanna get an engineer to calculate or perhaps start with smaller holes and widen them slowly.

Air dust filter - This is important but do note that it will slow down the air flow coming in a little depending on wat air filter type u put, be it G3/G4/etc filter.

Rain and air intake area - This is important. Since u have ALOT of airflow going in and out of your small room, u gotta make sure the air intake does not pull in water as well. I suggest having the direction of air coming in not point directly at your miners as it may bring some water in. For example, the intake air comes in through a duct that face downward to the ground, making the air come in facing downwards. This way, if any water droplets gets pulled in, it will drop to the floor. I suggest leave some distance between air intake and shelves. Same with exhaust, u may need to push the air through a fan through a duct due to rain, depends on situation.

If u have the space and it is economical enough, u may want to split it into 3-4 exhaust fans rather than 2, so that if one fails, u still have 2-3 working. Alternatively, u may wanna try get an electrician to use control circuitry with your box fans (if your box fan has that function), to wire it to the distribution box such that if the box fan fails, it shuts off the power at distribution box. This is because if box fan fails, your machines will overheat and the miner goes into overheat protection mode which works fine but I juz rather avoid. However, not all electricians know how to do this, juz fyi. May cost abit also.


Electrical -
Best to use power factor of 0.8 - 0.85.
Since it is on 24/7, this is continuous load, do not put more than 80% load on a breaker. Meaning if it is 20amp breaker, put at most 16 amp on it. Same with each socket, best to put more sockets and dont overload.
Make sure your wires are all good copper wires that are big enough. U dont want them overheating.
Use good mcb like hager or MK. Dont use cheap china mcb which may cause issues.
I use a surge arrestor for the distribution box to prevent surges. U may want one.

[brokenarrow2]

@Sandal_hat, thank you very much for the very detailed answer.

SHELVES:
These mining rig cases will be used (Veddha 8GPU Mining rig case: https://i.ebayimg.com/images/g/QpcAAOSws1ZZs276/s-l300.jpg), they can be stacked, and no shelves are needed. The downside is that you have to take all off, if you need to remove and service the bottom one. Is there any other advantage for using shelves? Perhaps higher distance between each rig, and the shelf between, so air doesn't go up to the above rig?

FAN:
On the image above, the fan is misplaced, the idea was to have it centered in the room. I guess two fans would be good for backup, but it's probably much more expensive, since each will have it's controller etc, but of course, no fan running at all with no mining would be very costful too.

How much air volume is your fan moving, and what is the average temperature inside your mining room, and outside?

I got a recommendation from a ventilation guy using this formula:

V = 3P/T2-T1.
 
V = Air volume (m3/h)
P = Power consumption to exhaust (W)
T1= Outside temp (ºC)
T2= Max temperature in mining room  (ºC)

In an example during summer, where it can be 25ºC, and I want the room to be 30ºC or less:
3x30000/30-25 = 18000 m3/h.

With a pressure drop due to ducts 250Pa he recommended a fan with these specs:
Air flow: 31500 m3/h
Max pressure: 600 Pa
Weight: 94 kg
Sound: 74-77 dB (yeah I guess that's pretty loud?)
Consumption: 3kW
Fan diameter: 1020 mm
RPM: 1450

How does that sound? It sounds HUUGE to me.. Price for that is about 4500 USD if i try to convert it. Plus controller, sensors, accessorier.
The weird thing is that I find lots of fans on Alibaba for $200-300. How can it be so much cheaper? I don't have to ship it, but it's still 4-5 weeks shipping.

I'd rather make it bigger than it needs to be, and be done with it, than change it in a year.

Great idea about the vents directed away from the machines.

Thanks again!

[polymer_city2]

I have 27 D3’s and 1 x S9in a tiny room in a warehouse.

I had huge issues with cooling to start.

I resolved this pretty easily.

400 mm intake fan into cold isle at low level

A 600 mm mobile fan in centre of cold isle facing upwards

600mm exhaust fan in centre of wall on hot isle.

The fans were from eBay around £250-£400 each.

I have control software which then lowers / raises frequency according to antminer temperature.

The 600mm fan is probably only slightly quieter than the 28 antminers that are running!

I’ll get a pic up if it will help

[Sandal_Hat]

@Sandal_hat, thank you very much for the very detailed answer.

SHELVES:
These mining rig cases will be used (Veddha 8GPU Mining rig case: https://i.ebayimg.com/images/g/QpcAAOSws1ZZs276/s-l300.jpg), they can be stacked, and no shelves are needed. The downside is that you have to take all off, if you need to remove and service the bottom one. Is there any other advantage for using shelves? Perhaps higher distance between each rig, and the shelf between, so air doesn't go up to the above rig?

FAN:
On the image above, the fan is misplaced, the idea was to have it centered in the room. I guess two fans would be good for backup, but it's probably much more expensive, since each will have it's controller etc, but of course, no fan running at all with no mining would be very costful too.

How much air volume is your fan moving, and what is the average temperature inside your mining room, and outside?

I got a recommendation from a ventilation guy using this formula:

V = 3P/T2-T1.
 
V = Air volume (m3/h)
P = Power consumption to exhaust (W)
T1= Outside temp (ºC)
T2= Max temperature in mining room  (ºC)

In an example during summer, where it can be 25ºC, and I want the room to be 30ºC or less:
3x30000/30-25 = 18000 m3/h.

With a pressure drop due to ducts 250Pa he recommended a fan with these specs:
Air flow: 31500 m3/h
Max pressure: 600 Pa
Weight: 94 kg
Sound: 74-77 dB (yeah I guess that's pretty loud?)
Consumption: 3kW
Fan diameter: 1020 mm
RPM: 1450

How does that sound? It sounds HUUGE to me.. Price for that is about 4500 USD if i try to convert it. Plus controller, sensors, accessorier.
The weird thing is that I find lots of fans on Alibaba for $200-300. How can it be so vmuch cheaper? I don't have to ship it, but it's still 4-5 weeks shipping.

I'd rather make it bigger than it needs to be, and be done with it, than change it in a year.

Great idea about the vents directed away from the machines.

Thanks again!

At first, I wanted alot of fan power (based on wat I read on the net and some calculations) but the engineer recommended me about 5000 cmh and I end up putting about 5500 CMH only. I can control the fan speed via a controller but I just leave it on near full power. I only lower the fan for a couple of seconds when I change air filter paper. If I buy an additional slide-in panel for the filter, I can probably change it by juz changing the whole panels and not the filter paper. I wouldnt need the fan speed controller then lol and can juz leave it at full power. I dont use any sensors, juz a simple fan speed controller, something like this http://img.directindustry.com/images_di/photo-mg/5369-9723484.jpg  . I skip using those expensive variable speed drives....dont need it lol.
 
My area is about 24-32 degrees and weirdly, I can get around 30 degrees inside when outside is 32 degrees but this is on the cold side of the miners. I never measured the hot side as the air is bound to be hot. More importantly, there is only 1 row of shelves and all the hot air goes into a sort of collection area and is immediately thrown out by the fan.


I wonder if 18,000 cmh is overkill. Anyways, more airflow cant be wrong. Bare in mind, 18,000cmh is huge, and so if any water gets pulled in the intake duct, it is going to pull the water quite alot in the direction of air flow. Also, the exhaust fan may push the air outside quite strongly for a few meters. Do note, u dont want trees receiving that warm exhaust air as they will probably die. U should check how far forward the air will be pushed out and if that will affect other stuff. Also, make sure the exhaust hot air cannot come back in if the wind changes direction. For my setup, the middle to bottom portion of the room has little more airflow and thus, is abit cooler to put all my miners there, rather than on top portion.

Your antminers will be far louder than your fans. There are far cheaper fans on amazon also. I used an expensive box fan due to the need to fix it with ducting, a fan speed controller and I also rig it to off the distribution box if it were to malfunction.

I have 27 D3’s and 1 x S9in a tiny room in a warehouse.

I had huge issues with cooling to start.

I resolved this pretty easily.

400 mm intake fan into cold isle at low level

A 600 mm mobile fan in centre of cold isle facing upwards

600mm exhaust fan in centre of wall on hot isle.

The fans were from eBay around £250-£400 each.

I have control software which then lowers / raises frequency according to antminer temperature.

The 600mm fan is probably only slightly quieter than the 28 antminers that are running!

I’ll get a pic up if it will help

How many CMH of fans is the exhaust fan? By right, if u push air outside, air will automatically come in, u dont need an intake fan.
The centre fan helps cool the miners? What temps u have outside and wat are your antminer temps?

For my setup, the middle to bottom area has more air flow and is abit cooler to put machines there then right at the top. So, I place all my asics there lol

[mettalmag]

@Sandal_hat, thank you very much for the very detailed answer.

SHELVES:
These mining rig cases will be used (Veddha 8GPU Mining rig case: https://i.ebayimg.com/images/g/QpcAAOSws1ZZs276/s-l300.jpg), they can be stacked, and no shelves are needed. The downside is that you have to take all off, if you need to remove and service the bottom one. Is there any other advantage for using shelves? Perhaps higher distance between each rig, and the shelf between, so air doesn't go up to the above rig?

FAN:
On the image above, the fan is misplaced, the idea was to have it centered in the room. I guess two fans would be good for backup, but it's probably much more expensive, since each will have it's controller etc, but of course, no fan running at all with no mining would be very costful too.

How much air volume is your fan moving, and what is the average temperature inside your mining room, and outside?

I got a recommendation from a ventilation guy using this formula:

V = 3P/T2-T1.
 
V = Air volume (m3/h)
P = Power consumption to exhaust (W)
T1= Outside temp (ºC)
T2= Max temperature in mining room  (ºC)

In an example during summer, where it can be 25ºC, and I want the room to be 30ºC or less:
3x30000/30-25 = 18000 m3/h.

With a pressure drop due to ducts 250Pa he recommended a fan with these specs:
Air flow: 31500 m3/h
Max pressure: 600 Pa
Weight: 94 kg
Sound: 74-77 dB (yeah I guess that's pretty loud?)
Consumption: 3kW
Fan diameter: 1020 mm
RPM: 1450

How does that sound? It sounds HUUGE to me.. Price for that is about 4500 USD if i try to convert it. Plus controller, sensors, accessorier.
The weird thing is that I find lots of fans on Alibaba for $200-300. How can it be so vmuch cheaper? I don't have to ship it, but it's still 4-5 weeks shipping.

I'd rather make it bigger than it needs to be, and be done with it, than change it in a year.

Great idea about the vents directed away from the machines.

Thanks again!

At first, I wanted alot of fan power (based on wat I read on the net and some calculations) but the engineer recommended me about 5000 cmh and I end up putting about 5500 CMH only. I can control the fan speed via a controller but I just leave it on near full power. I only lower the fan for a couple of seconds when I change air filter paper. If I buy an additional slide-in panel for the filter, I can probably change it by juz changing the whole panels and not the filter paper. I wouldnt need the fan speed controller then lol and can juz leave it at full power. I dont use any sensors, juz a simple fan speed controller, something like this http://img.directindustry.com/images_di/photo-mg/5369-9723484.jpg  . I skip using those expensive variable speed drives....dont need it lol.
 
My area is about 24-32 degrees and weirdly, I can get around 30 degrees inside when outside is 32 degrees but this is on the cold side of the miners. I never measured the hot side as the air is bound to be hot. More importantly, there is only 1 row of shelves and all the hot air goes into a sort of collection area and is immediately thrown out by the fan.


I wonder if 18,000 cmh is overkill. Bare in mind, 18,000cmh is huge, and so if any water gets pulled in the intake duct, it is going to pull the water quite alot in the direction of air flow. Also, the exhaust fan may push the air outside quite strongly for a few meters. Do note, u dont want trees receiving that warm exhaust air as they will probably die. U should check how far forward the air will be pushed out and if that will affect other stuff. Also, make sure the exhaust hot air cannot come back in if the wind changes direction.

Your antminers will be far louder than your fans. There are far cheaper fans on amazon also. I used an expensive box fan due to the need to fix it with ducting, a fan speed controller and I also rig it to off the distribution box if it were to malfunction. Also, it is only 1 fan and once fixed, I dont wanna move it.

I have 27 D3’s and 1 x S9in a tiny room in a warehouse.

I had huge issues with cooling to start.

I resolved this pretty easily.

400 mm intake fan into cold isle at low level

A 600 mm mobile fan in centre of cold isle facing upwards

600mm exhaust fan in centre of wall on hot isle.

The fans were from eBay around £250-£400 each.

I have control software which then lowers / raises frequency according to antminer temperature.

The 600mm fan is probably only slightly quieter than the 28 antminers that are running!

I’ll get a pic up if it will help

How many CMH of fans is the exhaust fan? By right, if u push air outside, air will automatically come in, u dont need an intake fan.
The centre fan helps cool the miners? What temps u have outside and wat are your antminer temps?

it is better to also use intake ones to reduce load on exhaust fans

[Sandal_Hat]

@Sandal_hat, thank you very much for the very detailed answer.

SHELVES:
These mining rig cases will be used (Veddha 8GPU Mining rig case: https://i.ebayimg.com/images/g/QpcAAOSws1ZZs276/s-l300.jpg), they can be stacked, and no shelves are needed. The downside is that you have to take all off, if you need to remove and service the bottom one. Is there any other advantage for using shelves? Perhaps higher distance between each rig, and the shelf between, so air doesn't go up to the above rig?

FAN:
On the image above, the fan is misplaced, the idea was to have it centered in the room. I guess two fans would be good for backup, but it's probably much more expensive, since each will have it's controller etc, but of course, no fan running at all with no mining would be very costful too.

How much air volume is your fan moving, and what is the average temperature inside your mining room, and outside?

I got a recommendation from a ventilation guy using this formula:

V = 3P/T2-T1.
 
V = Air volume (m3/h)
P = Power consumption to exhaust (W)
T1= Outside temp (ºC)
T2= Max temperature in mining room  (ºC)

In an example during summer, where it can be 25ºC, and I want the room to be 30ºC or less:
3x30000/30-25 = 18000 m3/h.

With a pressure drop due to ducts 250Pa he recommended a fan with these specs:
Air flow: 31500 m3/h
Max pressure: 600 Pa
Weight: 94 kg
Sound: 74-77 dB (yeah I guess that's pretty loud?)
Consumption: 3kW
Fan diameter: 1020 mm
RPM: 1450

How does that sound? It sounds HUUGE to me.. Price for that is about 4500 USD if i try to convert it. Plus controller, sensors, accessorier.
The weird thing is that I find lots of fans on Alibaba for $200-300. How can it be so vmuch cheaper? I don't have to ship it, but it's still 4-5 weeks shipping.

I'd rather make it bigger than it needs to be, and be done with it, than change it in a year.

Great idea about the vents directed away from the machines.

Thanks again!

At first, I wanted alot of fan power (based on wat I read on the net and some calculations) but the engineer recommended me about 5000 cmh and I end up putting about 5500 CMH only. I can control the fan speed via a controller but I just leave it on near full power. I only lower the fan for a couple of seconds when I change air filter paper. If I buy an additional slide-in panel for the filter, I can probably change it by juz changing the whole panels and not the filter paper. I wouldnt need the fan speed controller then lol and can juz leave it at full power. I dont use any sensors, juz a simple fan speed controller, something like this http://img.directindustry.com/images_di/photo-mg/5369-9723484.jpg  . I skip using those expensive variable speed drives....dont need it lol.
 
My area is about 24-32 degrees and weirdly, I can get around 30 degrees inside when outside is 32 degrees but this is on the cold side of the miners. I never measured the hot side as the air is bound to be hot. More importantly, there is only 1 row of shelves and all the hot air goes into a sort of collection area and is immediately thrown out by the fan.


I wonder if 18,000 cmh is overkill. Bare in mind, 18,000cmh is huge, and so if any water gets pulled in the intake duct, it is going to pull the water quite alot in the direction of air flow. Also, the exhaust fan may push the air outside quite strongly for a few meters. Do note, u dont want trees receiving that warm exhaust air as they will probably die. U should check how far forward the air will be pushed out and if that will affect other stuff. Also, make sure the exhaust hot air cannot come back in if the wind changes direction.

Your antminers will be far louder than your fans. There are far cheaper fans on amazon also. I used an expensive box fan due to the need to fix it with ducting, a fan speed controller and I also rig it to off the distribution box if it were to malfunction. Also, it is only 1 fan and once fixed, I dont wanna move it.

I have 27 D3’s and 1 x S9in a tiny room in a warehouse.

I had huge issues with cooling to start.

I resolved this pretty easily.

400 mm intake fan into cold isle at low level

A 600 mm mobile fan in centre of cold isle facing upwards

600mm exhaust fan in centre of wall on hot isle.

The fans were from eBay around £250-£400 each.

I have control software which then lowers / raises frequency according to antminer temperature.

The 600mm fan is probably only slightly quieter than the 28 antminers that are running!

I’ll get a pic up if it will help

How many CMH of fans is the exhaust fan? By right, if u push air outside, air will automatically come in, u dont need an intake fan.
The centre fan helps cool the miners? What temps u have outside and wat are your antminer temps?

it is better to also use intake ones to reduce load on exhaust fans

I see but isnt it better to just put the intake fan to exhaust?

[griffoncoin]

If you are in UK then I can offer you a rack in datacentre. I also keep all my stuff there.

[brokenarrow2]

@polymer_city: How many Watts do you have in that room? Cheap fans sounds nice, as long as they are built to run 24/7, but how do you get the air out of the building, do you have any ducts? Yeah a picture would help if you can arrange it. If you have any ebay links and/or specs of the fans it's interesting.

@Sandal_hat: Yeah, 18000 cmh is really huge, and I guess I agree with you about overkill control setup. Just a knob to adjust it to see what happens would be fine, but maybe some electricity can be saved by not pulling more air than necessary. The fan is rated 3kW on max, but if 6-7000 would be enough I guess it'll be cheaper, and even cheaper in the winter.

@griffoincoin: sorry, not in UK. How is the data centre cooled, I guess a data center full of miners is much more hot than regular web servers and such...

[crazydane]

I'm looking at a similar heat load.  Been looking at these 10,500 CFM fans for around $400:

https://www.northerntool.com/shop/tools/product_200422375_200422375

200 CFM per 1,500 watt miner means I could do about 50 GPU rigs or ASIC's with one of those fans, as long as I have unrestricted airflow.  So even if I loose 50% to intake filters and what not, that still leaves 5,000 CFM of air flow.  5,000 / 200 x 1,500 = 37,500 watts my miners can put out.

The fan above uses 3.5A at 230V, so that is about 800 watts.  That's about 13 CFM per watt, so quite efficient.

Any negatives to using fans such as the above?

Spec sheet:

https://www.jdmfg.com/wall-master-exhaust-fan

[brokenarrow2]

@crazydane: Looks good, can't figure out why the fan I got quoted was almost 10 times more expensive...

In my case I probably need a ceiling fan, which apparently is a bit more expensive, but not that much..

Whoa, your fan is 10500 CFM, which is 17800 CMH (M3/H). Just take note of the difference in case anyone stating CMH instead.
You can double check with the formula I wrote, with inside/outside temp but note it's for m3/h.

I'm not sure, but your fan seems to have 1/2 hp, if i use an online calculator, that is 0.3kW. "My" fan was 3kW, so it might be 10 times stronger, but I don't know how it's calculated. I guess more power is important with longer ducts and filters.

Let me know what you figure out!

[polymer_city2]

@brokenarrow

I’m going to the farm to knock it down tomorrow as the landlord doesn’t like the noise.  

It’s like 96dB or something stupid. May have made that number up...  

So I will get some pics before it all goes.

I’m running about 28kW.

I’m thinking to move it to a lead lined container I have access to.

The warehouse is huge, so I didn’t have any issues with re-circ on the heat.

Industrial Ventilation Extractor Metal Axial Exhaust Commercial Air Blower Fan https://rover.ebay.com/rover/0/0/0mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F40138896289

Also...

I had a quote for custom ventilation to be made for same size room
2 x intake & ducting
5 x exhaust fans (5 was recommended number)
And cowling and muffler / silencer
Around £1000

[jstefanop]

I'm looking at a similar heat load.  Been looking at these 10,500 CFM fans for around $400:

https://www.northerntool.com/shop/tools/product_200422375_200422375

200 CFM per 1,500 watt miner means I could do about 50 GPU rigs or ASIC's with one of those fans, as long as I have unrestricted airflow.  So even if I loose 50% to intake filters and what not, that still leaves 5,000 CFM of air flow.  5,000 / 200 x 1,500 = 37,500 watts my miners can put out.

The fan above uses 3.5A at 230V, so that is about 800 watts.  That's about 13 CFM per watt, so quite efficient.

Any negatives to using fans such as the above?

Spec sheet:

https://www.jdmfg.com/wall-master-exhaust-fan

10k CFM seems pretty overkill to me. Im running a single exhaust fan: https://www.amazon.com/gp/product/B002TXL5P0/ref=oh_aui_detailpage_o04_s01?ie=UTF8&psc=1

1.6k CFM for ~ 15kw worth of miners. Temps are about 10 degrees above outside.

[thisismyback]

10k CFM seems pretty overkill to me. Im running a single exhaust fan: https://www.amazon.com/gp/product/B002TXL5P0/ref=oh_aui_detailpage_o04_s01?ie=UTF8&psc=1

1.6k CFM for ~ 15kw worth of miners. Temps are about 10 degrees above outside.
[/quote]

Agreed. I'm running roughly the same but using a single exhaust fan with a max of 3560 CFM. http://www.airkinglimited.com/page/window-fan.html

It's doing a great job so far. Will prob have to add a second soon as I add more miners.