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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?"
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!
Dry ice and a fan?
This is not recommended:
Due to the health risks associated with carbon dioxide exposure, the U.S. Occupational Safety and Health Administration says that average exposure for healthy adults during an eight-hour work day should not exceed 5,000 ppm (0.5%). The maximum safe level for infants, children, the elderly and individuals with cardio-pulmonary health issues is significantly less. For short-term (under ten minutes) exposure, the U.S. National Institute for Occupational Safety and Health (NIOSH) and American Conference of Government Industrial Hygienists (ACGIH) limit is 30,000 ppm (3%). NIOSH also states that carbon dioxide concentrations exceeding 4% are immediately dangerous to life and health.
You have less than $2500.00 in cost there. Cripes the Libert unit in the server room here cost me $15,000 to have complete. $600 is dirt cheap $2500 is dirt cheap for what you are looking at.
Even if you did the Half-arse way and put 4 window air conditioners in the wall you still need the electrician to run wires.
You'll still come out the same price.
Do not look at laser with remaining good eye.
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!
In your posting you talked about adding ducts to steal A/C from a second unit. To work decently you would need to not only add a new output duct 'run', but also a new return 'run' (that is, unless the 2 units share a network of return ducting).
Does it hurt to hear them lying? Was this the only world you had?
Your solution *sounds* nice, but in fact, may drive cooling bills UP.
Where I live, it's routinely over 100 degrees (Yup. Ima 'merkin!) outside, today is expected to hit over 110. In order to provide a net savings, the hot air coming out from your server rack has to be even hotter than that, otherwise you're venting 90 degree air outside, then having to compensate for this by cooling down 110 degree air as it gets sucked into your building.
And this problem is exacerbated if there is relatively high humidity. (EG: Florida) Then, not only are you cooling down the air, you're pumping water out of the air, and since OP mentioned water drains and "not flooding" the place, this may well be him.
Now, if you're in an area where high temps are the exception, this may not be much of an issue. But it sure wouldn't work where I live.
OP: Here's what you do: Go to three reputable contractors. Get three quotes for the job. Get references for each contractor. Present this information to your boss.
If he/she can't handle that, you need to move on anyway.
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Looking at the cooling issue more broadly, here are a couple of resources that provide good information on techniques to optimize cooling on a budget:
The Hot Aisle: Great blog from Steve O'Donnell with practical ways to implement hot-aisle or cold-aisle containment and economizers.
Data Center Knowledge: Recent articles look at "roll your own" thermal monitoring solutions and using excess heat in swimming pools and greenhouses.
Not to mention-- adding another AC unit without that unit being tied into the same controller will cause problems for your AC units. They'll be turning on and shutting off more frequently. This will greatly affect the life of your AC units. If you're a hardware hacker, you can probably add capacity on the cheap by hacking your thermostat to coordinate multiple units. Otherwise, you really do just need to pony up and pay for the AC upgrade. Cool air is a basic business expense nowadays. If the people writing your budget don't see it that way, then your company is in trouble.
True, but condensation can't be an issue anyway. The compressor and condenser must be outside, or you'll just have a fancy heater that blows cold air on one side and drips water on the floor. See the laws of thermodynamics for details.
Funny you should come up with that retort. 2000/2001 I was a network admin at the South Pole. We had a door to open, about 1' square, to open to atmosphere if the room got to hot. Mind you, there was a 4 inch ice "berm" around the entire room. It made cooling my beer easier.
A defense contractor in Antarctica is a bad idea. Get Raytheon OUT of Antarctica.
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.