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Cooling the Server Room?
kolchak asks: "As the Australian summer heats up, we are looking at a cooling solution for our computer room. We have 4 racks (almost all full) with around 40 machines, switches, routers, 2 UPSs and 2 monitors. Unfortunately, its located in the middle of the office with no windows available for ventilation. We can vent the exhaust into the ceiling space which in turn is vented outside. Also, since the room is so small, we need to install any cooling device outside the room (a store room backs on which will house the cooling unit and potentially pipe hot / cold air through the wall). All the units we've seen so far need to be in the room, we just don't have the space. Anyone come across and solved this? Any ideas on good cooling units we can install easily and cheaply?"
We've got a similar problem, except that it's the winter time is the hardest to keep the room cool. During the summer, we run the air conditioner enough for the rest of the building that we can use the building's AC to keep the room nice and comfortable.
During the winter, however, the room is near the furnace, and I have a difficult time getting rid of the excess heat.
Our solution (such as it is) is to install a window unit AC in the room and vent the heat into the surrounding area. During the winter time, the heat zone that the room is in constantly runs the "fan only/no heat" option - it definitely helps the server room, but makes some of the other rooms less comfortable.
Our ultimate solution is to eventually move the server room, when that's possible.
A fine is a tax you pay for doing wrong and a tax is a fine you pay for doing all right.
one of the best solutions I have seen was at a local isp. They ran copper tubing just above the ceiling (hidden by the foam tiles) in a switchback layout similar to a radiator. They had a small pump just outside that moved water through both the internal and external radiators. It worked quite well and lowered the temperature in their main room by 20 degrees. Wasn't the prettiest thing with the tubing on the outside, but I'm sure you can find a way to hide it.
Ohhhh, look at all the pretty shiny things.
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I'll boil it down for you:
1: Get professional help (arch, engineer, contractor)
2: Repeat #1.
"As God is my witness, I thought turkeys could fly." A. Carlson
We have a phone closet and a computer room with a similar configuration (4 full racks, 2 UPS etc). We use a 12kBtu split system in our phone room, and are installing a pair of 24kBtu units in our main computer room. You can get a lot of types of them, the cheapest and easiest hang on the wall. They use a couple of pipes running outside or to the roof to the condensers. The condensers themselves are really small (compared to a single package unit). The systems we are putting in our computer room are about 6 grand apeice.
In your situation, you just run the piping through the plenem to an outside wall. You can toss the condensers just about anywhere (tho you probably want to make sure there is room to fence in the slab so some smartass cant just walk up and turn off your AC.
Here's a wild idea...Go hire some engineers.
Apparently there are whole companies who specialize in heating and cooling.
That will probably work out better than asking a bunch of geeks for a hack without knowing any of the details...
I suggest keeping your units a good distance away from the wall and floors so that the air you move will move freely and dissapate as much as heat as possible, keep backs of racks and cabinets off to help air move, should also help. Using a cardboard or tin plate on front ot you airconditioner, cut out holes to match the diameter of a clothes dryer vent pipe/tube (two or three, I think they are about 5-6 inches diameter), then lead the air wher you need it.
I eat my grapes at room temperature, cuz the cold ones hurt my teeth
See, I live in Wisconsin. And it's starting to get kind of cold. We'll let you run an air duct from here to Australia and take our cold air, if you put in another air duct blowing some of your warm air back here. Give us a call and we'll talk it over.
...
What you want is called split system air conditioning.
Outside you have a condensing unit that can sit on the ground or the roof, inside you have a fan coil. The two are connected via 50-100 ft of insulated copper pipe.
There is little ductwork involved, the fan coil sits in the ceiling space and simply recirculate and cools the air within the room.
Typically a configuration like this would run up to 5 tons of cooling, which is about 17KW worth of heat removed from your computer room.
If you need more cooling you can install more units.
Contact a local refrigeration contractor or refigeration equipment supplier for help, they are generally quite helpfull if they think they might get a sale out of it.
They generate more heat than they take away, and you'll have trouble exhausting away all the heat they produce.
1 watt-hour == 3.41 BTUs. Say your typical rackmount PC, without monitor, draws around 100 watts, that's 341 BTUs. 40 machines plus two monitors and UPSs, plus some odd heat from lights and whatnot, call it about 14,000 BTUs. All that heat rises, and the best thing to do with it is duct it away, then replace it with cold air.
DO NOT SIMPLY DRAW IT INTO THE DROP CEILING, unless there is predictable airflow beyond the ceiling tiles, or a duct, with negative pressure relative to the server room. If there is not a definite exit from the ceiling, or if you're just pushing it up there and hoping it ends up someplace else, forget about it, it just lingers.
Portable AC-on-wheels: they generate decent BTUs removal, but their exchaust is ferocious. If you must use one, cut a hole in the wall for the exit hose, or mount it in a nearby window, just get it away. Don't even think of emptying it into the walls or drop-ceiling, it'll linger and boost the ambient temp.
If you have a window within 50 feet, you could mount a 20-25,000 BTU AC unit, and send the output through an insulated duct to the server room. If the duct runs more than 20-25 feet, you should put a draw fan on it to reduce back-pressure at the AC. Back-pressure can cause all sorts of trouble, so don't force through a tiny or too-long pipe.
Eh, if any of this seems confusing, hire a contractor!
The most important thing to do is monitor temperature in the room. If any of your PCs is recent, it'll have both "system" and "cpu" temp monitoring. There are temperature logging apps for *nix and Windows.
More beer please.
Big Daddy, Johnny, Burp, Aunt Zelda, Scott, Slurp, Big Momma
...you don't place your servers and build the server room around them. You build the server room first, then you place your servers. ...
so, for future reference, you put the cart before the horse.
...don't do this.
One thing is an absolute necessity: Redundancy. Make sure you have two (or more) completely separate units. Each unit should run at NO MORE than 50% of its total cooling capacity. Each has a completely separate power source, all the back to the utility hook up. Run ALL AC units, all the time. Don't plug one in and leave it turned off until you need to use it as a backup.
AC units will break down. You know this. When it happens, you will discover you have far less time to react than you think.
And if you don't have redundant cooling, you're gonna fry a lotta expensive hardware.
Pavlov wouldn't be so famous if he'd used a can opener instead of a bell.
First, it has to be said that when you built your server room you should have planned that before the equipment ever went in. Hindsight.
I'll pat myself on the back here. In my 911 PSAP and dispatch center we have a room that houses the phone system, servers and radios. I have to imagine that this room generates far more heat than what you're dealing with because of the transmitters. There was no environmental control, not even vents. Systems would die or reboot without warning all year round but the problem got worse in the summer.
Nobody knew what to do. Like your situation, this room is in the middle of the building. Every amateur carpenter, electrician, HVAC tech in the police department looked at it and scratched their heads.
Then I came into the picture. Rather than wasting time thinking about the problem or asking Slashdot, I picked up the phone and called the local HVAC shop. In minutes I had not one but two qualified technicians with over 30 years of combined experience at my disposal. Two hours later I had a quote. Three weeks later the temperature and humidity in the room are constant and within tolerance. And we haven't had a single equipment failure since.
The system they installed uses the building water supply to cool air in a machine down the hall. The cool air is vented into the room and exhaust is vented up through the roof. That vent work is amazing, none of us non HVAC techs would have guessed it to be possible.
Do yourself a huge favor and call in a pro.
. Quit playing Monopoly with Bill. Switch to one of many non-Microsoft products today.
Here in winter, we've shut down our rack fans, turned off ACs and are looking at ways to make ourselves warmer. We could use some aussi machines to help in this time of need. Canada has enough electricity to export
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