Server Room in Retro Fit Project

[m2e]

Hi,

I'm designing a retrofit project for a small office. Total area is 5,400 sq.ft. The office is located in an old 2-story office building where there's only one AHU serving everything. The office I'm working on doesn't have access to the t-stat. The client would like to put a server room in the office, but we do not have the chance to put any extra cooling unit of any kind into the space. That mean we can only redirect the existing ductwork to do temperature control.

The server room, right now only has one server, one monitor (usually off), one small UPS, and several routers and modems. Therefore, the load, I'm guessing would be below ~3000W (~10000 btu/h).

What is the best strategy to deal with this server room, with the limitation I have?

Thanks.

Michael

 

[KiwiMace]

Advise your client what he needs rather than be pushed into providing a solution that won't perform. Do you have the spare capacity in the main system? Does the server need cooling overnight, independent of the main system? Result of downtime? There are a lot of considerations that may change their mind.

 

[imok2]

If you can determine that the existing system has the required capacity to handle all the load then it's just a matter of installing a take off of the main duct with a damper and controller either pneumaticly of electrically with a low voltage Stat. However, like CinciMace said if you need to cool at off hours; you need to run the system all the time. Have you looked into a spot cooler?

 

[m2e]

I believe the existing system should be able to handle the load, because the load is small. You're correct, off hour may be a problem. I'm also concerned about when the main system is in heating mode during winter.. any suggestion on this? Just close it off with a motorized damper in winter?

Spot cooler seem to be a good idea. Could you give me some direction on this?

Thanks.

 

[imok2]

Here are a couple of web sites:

http://www.industrialspotcoolers.co...sessionid=qriupu3gf0uvr255rzk35a45&cc=us&ns=1

http://www.atlassales.com/

 

[Yorkman]

There are small ductless split systems that we've used for this situation (Mitsubishi?), they can go to I believe 3 tons and are pretty Quick to install.

I'm not a real engineer, but I play one on T.V.
A.J. Gest, York Int./JCI

 

[LSA]

I agree with York. I would use an independent system, such as an split system (i.e. mr slim). They have their won control and can operate 24/7.

Also, size your system for possible server expansion. You never know when they might consider adding more equipments.

 

[imok2]

The beauty of a spot cooler is that all you need to do is roll out the smaller unit and roll in the bigger one and the controls are built in you can lease it or buy it

 

[humpy]

When we have a server room(closet) to cool in a small office and a mini-split is cost prohibitive we usually install a exhaust fan in the ceiling capable of 5+ ACH and a door grille low. Discharge to plenum or outdoors depending on your air balance. Heating or cooling, you are running 70 degree air thru the room. I realize this is not ideal, but seems to be better than nothing. We usually put the exhaust fan on a cooling only t'stat so the tenant does not have to turn it on or off. Let me know if our thinking is flawed here. I'm only talking about a room with 1 or 2 normal desktop size servers and a monitor(50 sf +/-).

 

[KenRad]

I'm confused as to why spot coolers would be recommended for this application. If they are water cooled or split system, you could get your additional cooling capacity that way. But most of what we call "spot coolers" are the portable packaged type, like Movincool brand. Without dumping the heat outside the room, these will give the server room a net increase in heat load (condenser heat rejected must be more than cooling capacity).

The load on your computer room will be very different from the rest of the building. I believe that you are asking for trouble if you do anything other than a separate system for this room. Computer room owners can be very difficult to satisfy.

---KenRad

 

[redgdon]

I would agree with those advocating a split system.

I would also suggest that you would consider twin systems to ensure you have cooling should one system fall over. This will of course depend on how critical the server is to your client.