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These 2 rigs of 7950x4 are in my 3rd bedroom that is 10ft X 12ft.  Even with the two windows in the room open the room gets notably warm.  Soon to keep the rest of the house comfortable during the summer I will need to turn on AC.  This leaves me the option to close off this room from the AC and hope the windows can keep the rig cool during the summer or setup an exhaust system.

Ideas for the exhaust system.
-Make a box of Corrugated Plastic over this shelving unit allowing openings for the box fans to intake air into the box. http://www.homedepot.com/p/3-sq-ft-Plastic-White-Corrugated-Sheets-15-Pack-COR-2418-15/202038093#.UYvaDsqZuTI
-2 6" Start Collar With Crimp behind each set of 4 cards. http://www.menards.com/main/heating-cooling/ductwork/round/start-collars/6-start-collar-with-crimp/p-114674-c-6828.htm
-3 6" Standard Gauge elbow. http://www.menards.com/main/heating-cooling/ductwork/round/elbows/6-standard-gauge/p-115326-c-6821.htm
-1 6"x4"x4" Standard Gauge Wye. http://www.menards.com/main/heating-cooling/ductwork/round/wyes-tees/6x4x4-standard-gauge-wye/p-1494470-c-6832.htm
-1 6" ROUND IN-LINE DUCT FAN after the Wye. http://www.menards.com/main/heating-cooling/ductwork/indoor-air-quality/6-round-in-line-duct-fan/p-113772-c-6872.htm
-Some pipe up to the window.  Put a board in the window with a Aluminum Wall Cap for 6" Round Duct. http://www.menards.com/main/bath/bath-fans/aluminum-wall-cap-for-6-round-duct/p-189438-c-5869.htm
-Close the other window in the room and turn on the AC.

I would like to expand this to 4 rigs on this shelf. http://www.amazon.com/Whitmor-6070-267-Supreme-5-Tier-Shelving/dp/B000LRDTYG/ref=sr_1_2?ie=UTF8&qid=1368075114&sr=8-2&keywords=metal+shelving
A lot of this thought stemmed from these two videos. http://www.youtube.com/watch?v=G5f_e4P6gMA http://www.youtube.com/watch?v=NMbq2FB8nDE

Thanks

Did you see this thread: https://bitcointalk.org/index.php?topic=198676.0

Yes I did see that thread but I can't really cut a hole in the ceiling.  I search the forums a lot and didn't find much HVAC info surprisingly.

I believe during the summer you want to exhaust outside and during the winter you want to exhaust to the cool attic.

do you only have that one window?

it's too small for how I vent room, but I guess you could buy some cheap window ac?

oh, nm, i read on

with two windows, why can't you just put a fan in one window, seal off the rest of that window, then vent out the second window?

Too sum things up. I'm going to need central AC on for my family to survive the summer. I'm trying to come up with a plan to efficiently exhaust the miners heat without wasting my AC and driving my electric bill even higher.

Wouldn't using a window fan in the non exhaust window be blowing hot outside air into the room?  I figured the best solution would to just simply exhaust the rig and hopefully my central AC keeps things cool but I know nothing about HVAC.

Exhaust from WHERE? If you have a sealed room, you can't "exhaust" anything without drawing it in from outside first. Where do you think the exhaust is going? Outside. Okay, but where is the air coming from to replace it? You have two choices. You can blow out all the AC from your house, or you can draw some from outside ambient, and then exhaust it right back out.

The room is gonna be hot regardless. The question is whether outside ambient is hotter than the room is in the first place. If so, then flowing ambient temp air from outside is a better option than sealing the room.

If you're gonna waste AC resources, don't exhaust it outside, exhaust it down your air return of your AC, so it can be cooled back down.

Unless you're in AZ, your outside ambient is almost certainly going to be cooler than a sealed room, so you need an intake and an exhaust. You can use two halves of the window, if you use some ducting to direct the flow. Or you can use two different windows, preferably on opposite sides of the room.

HVAC is complicated, there's a reason why companies specialize in providing this service. If you don't mind wiring a bit you might consider hooking a high CFM shuttered fan to a thermostat, install it in a window and block off the excess space. Then pull in cool air from the house, circulate it in the room and set it to vent only above a certain temp. Downside is that unless insulated well you might pour warm air into the house causing the AC to run more, otherwise you are venting your AC air however. Neither is ideal.

Possibly the best would be hook up a swamp cooler to a window, blow cooler air over your rigs, then vent out opposite window. Not too expensive, electrically not too bad, keep the rest of the house separate. Only downside is if you are in a humid climate it won't work and can make excess moisture an electrical worry.

Honestly unless you live somewhere ridiculous, just cross venting with high CFM fans is the best.

Thanks for your replies guys.

This is my current build plan unless someone comes up with something better.  I’m not going to seal off this 3rd bedroom and I’m going to use central AC.  The goal is not to waste AC.

I’m going to make a corrugated plastic box around this shelf with openings for the box fans and an exit exhaust out the window in an attempt to create positive air flow pressure.

 

The question is should I use the window on an adjacent wall as an intake to this corrugated plastic box or let it just use the AC in the house?  The temp outside is currently 85F (29.4C).  Currently the GPUs report around 74-77C.  I don’t have a thermometer next to the rig but should probably get one.

Just throw the rigs outside  ;D

I actually considered that as I have a fairly large shed (probably 6ft X 12ft). But I'm sure it get to 100F in there in the Summer and I don't think fans would keep the rigs cool without AC.

I have an idea, but don't know if it's an good. Instead of blowing air horizontally like you do now, blow air from floor to ceiling. The cooler air is lower because of density and you blow that over the fans and up to the ceiling. Like this:

-----------------ceiling

[-------------] Miner
[-------------]

{^^^^^^^^} Fan blowing air up
|                  |
--------------------Floor

Probably a better recirculating setup?

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This is what I was thinking.  Any suggestions? Could u suggest a high cfm fan and where would u put the fan. I'd rather not go to an evap cooler just yet.

Seal the room up.  Turn off the central aircon to that room. 

Get a board that covers half of the window, fit a 6" fan to that, with piping that goes below your rig.  Leave the other half of the window open.  Air being sucked in from outside will blow through the rig, be heated and exhaust out the open side of the window.  Simple.

I have my entire computer top and back enclosed with 20 sheets of paper, taped up going to an exhaust pipe which goes to the window. Exhausts at least 80% of the heat, without any fans in the actual tubing.

I think you've got the right idea. Even if you did put it in your shed, you could put the system in an insulated housing, and use and exhaust fan system to circulate the cooler air from the outside through.

As somebody mentioned, make sure your cool air intake is at the lower portion of the case/housing and the heat exhaust is out the top.

Also, if you're going to be running the ducting anyway, lose the box fans, and condense your housing down. Install 1-2 of these in your exhaust ducting. http://www.use-enco.com/CGI/INSRIT?PMAKA=325-7358&cm_mmc=Didit-_-SEM-_-GglProd-_-GglProd&003=18299132&010=325-7358&{copy:002}&{copy:004}&{copy:005}&10=325-7358&gclid=CN3sxp3wi7cCFYx_Qgodr2IAKA

This will be far more efficient for the airflow and will ensure that your box fans don't create a positive pressure in the box that could actually hinder cool air from being streamlined  THROUGH the system, and rather just creates a funky little vortex of dead airspace in the ducting, trapping most of the head inside your housing.

Use the fans DESIGNED for this type of work, and you'll be happier overall.
Also, if you only have one window to use two halves of for your ducting, make sure to put an elbow that points down on the intake, and a stack to exhaust the hot air up a few inches, so that you're not just recirculating the same hot air back in.

I would avoid a swamp cooler, as humidity and electronics are mortal enemies.

Also, I would put a lot of thought into how you're going to direct airflow THROUGH the system, making the air pass completely through the first level, and then moving up to the second level; orienting components so that they get the best airflow through them, and so that the airflow works with any individual component fans that might be in the system. No offense, but looking at your existing setup, it looks like very little thought was put into how to route the airflow, and instead, a random fan was just pointed anywhere it might be able to fit...

Another option would be to do a water-cooling setup, with a radiator routed outside.

Thank you for your reply.

Moving to an isolated system with fresh air in the bottom and hot air out the top, the boards which the motherboards and box fan sit on would need to be rethought as they are now a barrier to air flow.  I can get rid of the wye then also and have one intake and one exhaust.  I have separate windows on different walls of the room to use one for intake, one for exhaust.  6" ducting large enough?

Would you put an inline fan like u linked in the intake and exhaust?

Ok getting rid of the box fans is fine but they will need to be replaced as the cards will need some sort of airflow across them I would think.  You mention using fans designed for this type of work.  Are you suggesting 120mm or something more powerful?

The fans I'm talking about is the duct fans. How many fans you need will depend on the rated CFM of the fan. I would put one in the exhaust duct for sure. If you find that it's not up to the task, you can add one on the intake.

I would remove the box fans, and then size down the box in order to force the air to flow. I made a quick crappy drawing to demonstrate the idea, but my work firewall has all the image hosting sites blocked...

I'll try and post it on my lunch in a few minutes.

EDIT:

Here's the crappy drawing. You can add as vertical baffles as well, to route the airflow even more specifically. This is just a general idea. As a rule, the less unneeded airspace in the box, the more efficient the airflow will be in removing heat. I would also insulate the box and ducting, to avoid having heat escape into the room, keeping your air conditioning more efficient as well.

Just a few ideas. There may be better ways of doing this, but this is how I'd do it. I'd also probably wire up the fans to some sort of thermostat system, maybe have one fan constantly running, but have the second one kick in if temps get higher than a pre-defined temp. You could get pretty fancy with it, but a simple design is probably the best starting point.

http://i141.photobucket.com/albums/r72/Uraijit/Airbox_zpsc4b58faa.jpg

This will work to some degree and is cheap.  Better yet would be to go to 12". 

Do yourself a favor and find a way to filter the incoming air. I ran a location last summer where I sucked in unfiltered air and ended up with a ton of unnecessary dust. This time around I'm using furnace air filter elements as I begin to vent heat outdoors again.

Thanks for all your tips.  I have rethought my rig and have figured out a way to make the cards sit exhausting up.  Construction to begin tomorrow, now that LTC diff went up 27% lol.  I'll have pics and other updates in a few days.  Risers should be in early next week.

Find an old dryer, or two old microwaves... Gut them, and put everything inside.

Vent out a window, also pull-in from outside. (Or you suck-out all your home AC)

90F is only 32C... that is cooler than the 65C-80C, which your cards operate at. (Thus, they will be adequately cooled from outside air.)

FYI, a cheap trash-can also makes a good "air-flow shroud". Not to mention a "bathroom fan" (the cheap ones), make great high velocity/volume air-flow. (Cheaper than those other fans too.)

I want to see a picture!

I want to see the picture after the fire department visits him... :P

Why not just gut a window-ac unit, and put the PC in there? Or, um... move the PC to the window, exhausting directly out there?  ???

yeah, i live in texas, sometimes it's 110oF outside here, but i was still able to keep all my cards at or below 80oC all last summer (except for once when one of my 5970 fans busted and when i went in there it was at like 105oC, hashing away at 50mhash/100mhash, throttled etc)..  they only hit 80oC on the hottest days in the afternoon, most maxed out between 70-75.  you'll probably need to lower the voltage.   110oF is 43oC, which was a lot cooler than the cards were running at.   you'll want to make sure you have good PSUs or they'll either be incredibly inefficient or just die in high ambient temps

some of that hot air escapes into the house, but not a whole lot, assuming that the only entry point to the rest of the house is the door to the room (yeah, we can assume a few cracks in the ceiling etc).  you can buy (or make) something to seal off at least the bottom of a door.  some air will escape out the side unless you improvise on that, not that much though (if you have proper exhaust)

i only have one window, you have two, so just put the computers between the two windows, you dont need a fan on the second window.  use a piece of paper to determine how far to open it, likewise if your sealing job on the first window isnt so hot, you can use some paper or a napkin or something to make sure air isnt escaping from that window

i wouldn't get too complicated or spend a lot of money on same fancy setup, since it's unlikely you'll be running the GPUs for more than a few more months??  unless you're a believer in scrypt alt-currencies

Cheapest way is to buy something you will use later...

Drywall is cheap. Doors can be too, free on the side of the road.

Box it in at the window. You only have to exhaust the top-hot air, shoot it out far enough that it does not get sucked back in by the intake. (The intake being cold, can be a simple cloth-sheet sock. (Cheap bedspread which you duct-tape to form a long-ass filter-sock. Throw a rock inside and let it hang down.)

Even cardboard would work, if you want to go ghetto-diy.

Exhaust top, cool at bottom, fans directing it all up, or just mixing it. The heat will rise, the cool will fall. (Less if you are just mixing it.)

When you are done, just disassemble it. Someone will buy the unused sheet-rock dry-wall. I am sure you will find a new purpose for it. (Life-time supply of driveway and sidewalk chalk for the kids!)

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Well I spent about $90 at Menards including the fan.  I'll hopefully finish the gpu rig enclosing 8 7950s tonight so I can hook it up to my window intake/exhaust.  More pics to come. Thanks for all your advice.

That's a man's work!... (no offence if you are a woman)

Perfect, now all you need is a gate-T so you can manually route heat into the house in the winter!

Don't forget to varnish that wood! (Or wax it)

You may want another intake, if that doesn't have a booster-fan in there too. Always have a larger intake than exhaust, because the exhaust is compressed and the intake is negative. You want to reduce negative pressure so it does not pull air from other doorways or windows or wall-outlets.

Those fans arn't really made to do that job, though depending on your container size, a few of them WILL get it done nicely. Just 1 is testing it IMO. What you really want is a centrifugal fan; 300+CFM, and made to overcome static pressure; loud and overkill mostly. The most well respect brand for quietness is Can-Fan.

But only 8GPUs you should be fine without that. Keep your gpu box as small as you can, another duct booster and you should be fine.

I'm not going to bother to varnish.  I may paint it white to further seal.  I plan to take it out in a few months after summer.  I assume GPU mining won't be profitable by next summer.  If the furnace was nearby I would vent it through the house but its not.

I had seen some pics of setups but didn't know a brand for those high power fans.  I'm going to test the temps before enclosing and then will add more of those cheap 6" duct fans if necessary to get things to work.

I didn't finish my 8 card case so I'll get it done in a day or so.  Some family things took priority.

The fans I linked are 500 CFM per fan...

I realize that.  But the cost is effecting the profits.
This fan (70W 334CFM) for $146 http://www.amazon.com/Can-Fan-Inline-6-Inch-Minute/dp/B004C2IWIE
This fan (138W 392CFM) for $124.99 http://www.thehydrosource.com/can-fan-inline-fans.html

Really though at that point might as well look at http://www.iaqsource.com/product.php?p=panasonic_fv-40nlf1&product=111092&utm_source=amazon-pads&utm_medium=cpc for $200.

Anyways I'm going to try and get by with these $30 6" duct fans.  If that won't pull enough hot air out then I'll look to bigger setups but will consider price.  I'll know by the end of this week.

Got a Can-Fan RS6HO for $65 shipped. www.ebay.com/itm/171037352963

Please tell me that is your garage/extension and not your house.......

If you need a fan, get one of these:

http://www.globalindustrial.com/p/hvac/fans/blower/portable-ventilation-fan-8-inch-with-16-feet-flexible-ducting

Very cheap without the piping... You're looking at about $130 for 2500 CFM and 400w power draw.

you could also add a small radiator/intercooler to your window inlet and hook it up to a self made cooling tower that vents outside so it doesn't raise humidity. wouldn't need much power at all, just a small water pump and another fan. Get some PVC and a misting shower head. Just add water.

Nice job on the setup, looks good.

I agree on the can fan though, get a good fan.  One 10" or 12" can fan will do the job significantly better than any amount of those dryer duct booster fans.  And grab a speed controller.

http://www.amazon.com/home-improvement/dp/B000HQAVNI

i've basically done this, works pretty well, i can help ya if you have any questions

https://bitcointalk.org/index.php?topic=7216.msg2423200#msg2423200 (https://bitcointalk.org/index.php?topic=7216.msg2423200#msg2423200)

500 cfm is a joke lol, a set of case fans do 500cfm, you need way more than that for 8 7950's

http://www.homedepot.com/p/B-Air-High-Velocity-3-Speed-3550-CFM-Air-Mover-Carpet-Dryer-Floor-Dryer-GP-1-GREEN/203074014?N=c4m7#.UbUCNkDvs1M

http://www.homedepot.com/p/B-Air-Powerful-5080-CFM-Air-Mover-Ventilator-Blower-BB-1/203074030?N=c4m7#.UbUCV0Dvs1M

Put a window mounted AC unit in that window and turn down your central AC a bit to compensate.

10" or bigger duct fan is the way to go. Something like in this picture will be enough for a room with +5kW of heat. Add a thyristor controller to find optimal speed and noise levels.

http://www.axair-fans.co.uk/news/wp-content/uploads/2013/02/In-line-duct-fan.jpg

 ::)

A single 500 CFM fan is enough to replace the entire volume of a 5 cubic foot case 100 times per minute. A pair of them, 200 times per minute... Are you drunk posting, or are you naturally this bad at math?