Slashdot Mirror
Cost-Effective Server Room Air Conditioning?
at0mic26 writes "I am currently tasked with finding a cost effective solution to our 30+ degree Celsius server room. The only air conditioning currently provided is a single duct pipe from one of two air conditioner units. I was thinking of stealing air from the second air conditioning unit with some sheet metal work, but it likely will not be sufficient — and would not have tolerance for both AC units being offline for any amount of time. An ideal supplemental portable AC unit is what I am after, however I'm finding it cost prohibitive, with $600+ humidity controlled AC unit, plus 20 amp socket requirement, plus contract work to make a hole in the wall for outside drainage so that the unit does not flood the place. What sort of successful cheaper air conditioning solutions have you come up with?"
Move the room to Antarctica, turn off the heat.
Need an automatic screenshot taker? Try here.
if you can't afford $600 to cool the room, you need to turn off your servers.
Dry ice.
Just imagine the theatrics.
Dry ice and a fan? Seriously though, there's not much you can do here. What is the cost to the business if hardware starts failing if it overheats? How does that compare with the total cost of installing another A/C unit?
There are no cheap A/C solutions. Portable home units lack the tonnage to adequate cool even a small bedroom, let alone a room full of fire-breathing servers. Industrial portables for 'spot' cooling, that have sufficient tonnage start in the low $10K rang and quickly move up. My suggestion is to get an A/C pro to do up the spec for you and then bid it out with guarantees and such in the RFP.
Sig this!
Never try and just make do with the cooling.
The cost of doing it right pales in comparison with not doing it right and something happening.
If you posted more information you could get a reasonable answer.
How much space?
How much heat is the equipment giving off?
What is your budget?
At what temperature do you want to operate the room?
How quickly is the heat output of the equipment growing?
How much excess capacity do you need?
If you can't answer those questions you won't get a workable solution.
You can use standard window units - but the key is insulation - you have to have a very well insulated and sealed room. I built my own server room by adding two additional layers of insulation on to the existing sheetrock (styrofoam with a plastic vinyl 4x8 sheet paneling and then putting silicon on all the seams, then using window units (with a backup unit). I can keep the room at a constant 61 degrees F with two full height racks running with a 8000-12000 btu 220 window unit.
The best idea I've seen is to use enclosed racks, sealed with weatherstripping except for vents at the bottom, and put a duct in the top that leads to an exhaust fan on the roof. Now you're not trying to cool the hot air produced by the servers; you're removing the hot air produced by the servers. Cool air from the already-air-conditioned room will be sucked up through ventilation at the bottom of the rack to keep the servers cool. And since your existing AC doesn't have to cool all that hot air, it should be able to keep the room temperature down to 20C.
Note that this is a long-term solution in terms of lower energy costs. I have no idea what it would cost up front to implement.
$x='S24;r)>63/* h@<5+oZ)32"5cz';$me='phroggy'x$];
$x=~y+ -xz+\0-Tx+;print$_^chop$me for split'',$x;
Seriously, the coward shitteth you not. If you can't afford $600 to cool the room, then consolidate your services onto fewer machines and shut the others off, because they're obviously not making you enough money to be worth running.
If, on the other hand, your boss is a cheapskate then do something like I did before - moved the servers out to my desk and stuck a honking big fan at one side to blow air past them. It had the very big plus side of being obvious to everyone that we had to keep the servers cool, and reminded them every day that the alternative was buying some aircon.
Bite the bullet and get what you need right the first time, because the repair and replace if it isn't done correctly will make $1500 seem like a drop in the bucket...
Physics is nothing like religion. If it was, we'd have an easier time trying to raise money!
from your budget, you clearly only have one server in play, so put it in a refrigerator.
Cut a hole in the door to let the cables in and seal around them with that expanding foam stuff in a spray can.
Sounds like that would max out your budget.
Nullius in verba
See! Problem solved!
Steven Wright has a line about "I bought a humidifier and a dehumidifier and put them together in a room to fight it out." That was what happened with our dual A/C system in the first computer room I helped build, back in the early 80s to support our VAXes. We had a couple of chilled-water Liebert units that were bigger than the computers, and management had decided to get two of them so we'd never lose cooling. Turned out we couldn't actually run them both at once, though I don't remember if they were fighting more about temperature or humidity - one unit would be pushing a bunch of cold dry air under the floor, which would blow into the sensors of the other unit, which would push a bunch of warm wet air under the floor, etc. And any time there was a power failure, the A/C wouldn't automatically restart, but the VAX would, so if this happened overnight or on a weekend, the room would reach 130 degrees (F), at which point the power system would decide their might be a fire and shut everything down until the room got cooler - which would take a while, since it wouldn't let us use the A/C. So we'd get in on Monday morning, have to open the back doors to the lab and go steal desk fans.
My late-90s lab had much smaller equipment - a bunch of routers and PCs in an enclosed office - but it still generated enough heat that we needed extra A/C. We didn't own the building, and the A/C unit that the landlord put in the ceiling would occasionally ice up and start dripping water onto our desk, but fortunately it usually missed the rack. For a couple of weeks during one of the A/C repairs, they gave us a big standalone thing that blew cool air into the room and warm air out through the ceiling ductwork. It had enough room in the top to chill a couple of bottles of wine, so our winetasting that month did whites.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
I once had to do essentially this in a slightly unusual situation: the server room was by an outside wall, and on the other side of the wall they were about to put in a new lawn. We just dug down extra deep (about 4 feet) and got about 100 feet of 6' diameter corrugated plastic drainpipe (intended to be buried, the corrugations make it somewhat flexible), covered it with dirt+lawn, and finally put a fan on one end and recirculated the server room air through this. Only had to buy a fan and the pipe, and the long-term power bills were almost zero (just the fan). And it's incredibly reliable.
"Let the room overheat and replace all the computing hardware. So what if you're down for a week?"
Don't forget the BOFH option. :)
Back everything up.
Wait until meltdown, then be the hero for restoring the new systems.
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
Yes, but it's a good rule of thumb that if the language has evolved at the hands of a business consultant, they're just trying to make an ordinary, everyday job description sound sexy and exciting through deliberate obfuscation and complication of syntax. "I've been tasked with getting a tiger team to think outside the box vis-a-vis their normal operational paradigm with regards to proactively seeking out new-media revenue generation through forward-thinking distribution channels" sounds a lot sexier to the average suit than "We need more money. What ideas do you internet nerds have?"
You have to ask the following questions when designing a cooling system for an HVAC system for a server room. The conditions are significantly different than cooling for an office.
1. What is your total kW consumed in the room.
2. What is the cooling strategy you want to employ?
Passive cooling - use a fan to dump the heat out of the building.
Active cooling - Install an air conditioner with an external condensing unit to dump the heat outside.
Alternate cooling - Dump the heat into the rest of the building during winter in order to saving on heating costs.
Any of these options have good and bad points: expense, humidity control, thermostat control, expense of use, required backups.
3. How is your server room arranged?
Is everything just thrown in the room?
Are you running a hot isle/cold isle environment?
Do you have a raised server floor so you can pump cold air into the bottom of the racks with a ceiling return?
Do the racks have fans to draw air from front to back?
4. What is your current cooling capacity that is dedicated to that room?
The last server room I designed was 500 square feet and consumed roughly 14 kw (28 watts/sf). That is roughly 4 tons of sensible cooling. To purchase a system capable of 4 tons of sensible cooling you will need to purchase a system capable of 5-6 tons of total cooling (Skipping the lecture on Sensible vs Latent vs Total cooling). So have you have just spent $4,000 in materials. Assume your costs will double for installation. Plus another couple of grand to have an actual engineer come in and design a system that will serve your specific needs.
The question is not one of getting the heat off the chips. The heat is making its way into the air just fine. You need to get the heat out of the air (and the room) and out of the building. If your room is exceeding 30C I would assume your racks are easily running 5-10 degrees hotter. That is getting into the range where your equipment is going to start shutting down.
Now onto your problem: $600 budget. Option: Throw a patch of your choice at it. A roll-a-way unit from Wal-mart or target where you can push a heat rejection duct out of the building, for example. This is a patch, not a solution.
Assume you are going to have to pony up $10,000 (USD) to solve this problem.
Architectural plans are like computer source code with a couple of differences: You only compile once.