Blowing some cool air on a hot server

March 15, 2012 6:08 AM

Apparently as the air system in our office building has degraded, the heat in our offices during the spring and fall when the AC shuts off has become unbearable as air that is hotter than outside is blown around. Bad for people, but worse for our server room. It has gotten to the breaking point and we need to do something. I'm looking for a way to cool off our servers in the transition periods between winter and A/C being turned on.

The server room is about 10' x 20' and has a 16' ceiling. It isn't air tight and there is maybe a foot or two between the ceiling tiles and the next floor.
There are four servers, a PC, a Dell MD1000 storage device, and three APC 3000VA UPS. There is no exhaust out from the room and there is a fan that blows in air (hot air at the moment, probably not A/C for a few weeks at least.)

The building is in the middle of a messy change of ownership and we can't really do much to reconfigure the room itself, at least not any time soon.

My current thought is to purchase a portable AC unit and have it vent out over the ceiling of the next room (this is doable). However I'm not sure how good of an idea this is or how strong of an AC unit to get.

I'm sure there are all sorts of details I'm leaving out - I'll clarify as best I can. I inherited this setup and a lot of things are undocumented or unknown. Also, it is going to be 80 degrees today and the quicker fix the better!

posted by charred husk to computers & internet (13 answers total)

Is there absolutely no way to get someone in to look at the HVAC system? A well-designed system should not lock out cooling if the outdoor air temp is 80F. The systems I design typically lock out cooling at or below OAT of 10C (50F).

During the shoulder seasons, mechanical cooling might be locked out based on outdoor air temp or a schedule, but free cooling via economizer dampers should still be available. Your problem could be from a badly designed system, a failed economizer/mixed air damper actuator, or any number of other things.

As far as your actual question, about the portable AC unit, I have seen that on multiple occasions. Hell, my own office used a Costco portable AC unit to cool our server room until we got the tinbashers to get some ducting in there. Ours vented to the outdoors though, and I can't say how good an idea it is to vent the AC unit into a ceiling space. The ceiling space could well be feeding into the main system loop and thus you might be indirectly heating your supply air even more. Might be worth calling a local mechanical contractor to see what they have to say. The pain in the butt will be that you are dumping hot air in from the main system that you are then cooling with the portable AC unit.
posted by Sternmeyer at 6:31 AM on March 15, 2012

There are portable, free standing air conditioners that you can rent that have two air outlets that are flexible tubes.

One tube will be cold air to direct at your server stack, the other will be hot air that you will need to vent...somewhere. Into the the plenum between the drop ceiling and the next floor is my first thought, but you may want to solicit a more expert opinion on that. Also, about once a day, someone will need to empty out a container that collects water that condenses from the cooled air.

Hit google or your local yellow pages for "air conditioner rental".
posted by de void at 6:33 AM on March 15, 2012 [1 favorite]

Sternmeyer: "Is there absolutely no way to get someone in to look at the HVAC system? A well-designed system should not lock out cooling if the outdoor air temp is 80F."

According to the front page expose on the sale of our building, the HVAC system is being held together with coat hangers. That reminds me, I need to change the filter on the portable air filter in the server room, too.

And it sounds like a portable AC unit should be okay. Maintenance said venting above the next room should be fine. The only question left is how big an A/C unit to get?
posted by charred husk at 6:42 AM on March 15, 2012

how big an A/C unit go get?

Charred, talk to the places that rent them, they should be able to advise. I think the term for what you're looking for is a "Spot Cooler".

Here's an example (not advocating this particular business):


posted by de void at 6:45 AM on March 15, 2012

Garr, my editing is atrocious this morning. Link should be:

http://www.portableac.com/
posted by de void at 6:46 AM on March 15, 2012

If the servers are in a rack, it may be worth your while to make a "door" of sorts that fits over the front of the rack and connects to the A/C unit, so that the cold air from the unit goes directly in the front of the servers. One portable A/C unit will do a lot more good cooling the small cubic volume of a rack than the entire closet.
posted by aaronbeekay at 6:55 AM on March 15, 2012

Do people work in the room whose ceiling you are venting into? I'm not an HVAC expert, but I imagine that this will raise the temperature of the next room by a fair amount. We have one of the free-standing AC units at home, and the vented air is hot.
posted by googly at 7:47 AM on March 15, 2012 [1 favorite]

How far away from the outdoors are you? Could you get something like a split system, where the condenser and compressor go outside, running the cooling lines through the drop ceiling space to the evaporator? (I've seen a model similar to these used in a server room before) The advantage is you can isolate your server room completely from your building HVAC, and cool your server room directly with your own equipment.
posted by defcom1 at 8:16 AM on March 15, 2012

I'll second googly's answer.
posted by buggzzee23 at 8:30 AM on March 15, 2012

I'd contact a lawyer, and consider documenting the problem, and escrowing rent, except for the money you spend to put in an air conditioner vented to the outside. Or to have someone come in, look at the existing system, and assist you in getting it resolved.

Look at your lease - it should specify what the landlord must provide, and what the tenant may do with the space. If you didn't tell them about a server room, it's harder to enforce making them cool it adequately. Even non-huge server rooms generate a lot of heat. But they still have an obligation to keep the office areas a reasonable temp.

The server room should have cooling and backup power for cooling and controlled shutdown in case of power loss.

Documentation: take temp readings several times a day, at the same time, in office areas and server room. If the office areas are uncomfortable, I'd alkso be concerned about air quality, and lack of adequate ventilation.
posted by theora55 at 9:36 AM on March 15, 2012

theora55: "I'd contact a lawyer"

Fortunately I work for law firm! They're talking with the potential new owners later today.

googly: "Do people work in the room whose ceiling you are venting into?"

No. It is next to the storage room.

de void: "Charred, talk to the places that rent them, they should be able to advise."

I checked around - a local company recommended I just buy one since the room was so small and I could almost buy one for the price they would charge me for a month.

Thanks everyone!
posted by charred husk at 9:49 AM on March 15, 2012

We used one of those portable ones with the flexable out house that goes into the plenum. They are good temporarily BUT stink when running 24 hours a day 7 days a week. IT will break down after about a year.

Its good temporarily but dont make it permanent.

Ours died and we are waiting for a company to come in and isntall one of those mitsubishi wall hanging units in our server closet.
posted by majortom1981 at 11:49 AM on March 15, 2012

majortom1981: "Its good temporarily but dont make it permanent. "

The building's AC isn't supposed to be turned on until April! But at least once that is done we can turn this one off. We should only need it for a month or two every year.

It's 72 outside and 88 in the office building! I saw Marcy Kaptur leaving her office and she didn't look thrilled. Hope whatever office she opens in Cleveland has better air than here.
posted by charred husk at 12:56 PM on March 15, 2012