Server Room Air Conditioning
Computer rooms have drastically changed in the past 15 years. Most of the behemoth sized systems are gone the way of the dinosaur. The Liebert and Edpac systems that took up the space of a large walk in closet and required costly elevated floors are now replaced with smaller systems that you could see in any small office. The reason for this is the increased capabilities of computer memory to reduce the size of the computers. We can now store as much memory on a laptop computer as we use to require a unit measuring 8 feet long, 7 feet high and 3 feet deep with additional space for the racks of magnetic tape. I have included a picture of the computer room at my old alma mater to illustrate the space requirements of old. The new updated systems would require an office maybe 6 ft. x 6 ft. The computer systems of old generated a ton of heat and required massive amounts of cooling and the magnetic tapes that were used generated so much static electricity that the rooms required costly steam humidification in the same units that were trying to cool the space. The A/C systems were just about as inefficient as the computer systems they were protecting.
New computer systems are not as temperature sensitive and can tolerate temperatures up to the low 80’s on the F. scale (approx. 27 C.). Many computer rooms for even large companies can be the size of a closet. The hard drives still generate heat, but at such a low rate that in most cases if the “closet” is properly ventilated, no additional cooling is required. Mind you, everything is relative. If you have a million dollars worth of computer equipment in a room it should not be out of line to spend 1 or 2% on A/C equipment to keep the space cool. Small systems can use a portable A/C unit similar to those made by Delonghi or General Electric that produce 10,000 BTU’s of cooling. These units are not intended for 24/7/365 use, however for the cost of the system it is worth replacing every two or three years. Moving into larger systems you have choices to install a dedicated roof top unit with a fresh air economizer that can provide year round cooling, a conventional split system A/C with the optional accessories to permit year round operation, a water cooled A/C where permitted (ideal for year round cooling applications) or a ductless split system A/C (see separate title in this section of our site for more info on ductless split A/C units)
No matter what system of the above you choose or your budget dictates, it is important to never install the equipment in the ceiling space of the computer room. Install the equipment exterior to the room and duct in the air flow. Sooner or later every mechanical system will fail and should a computer room unit fail, you could have water leak through the ceiling and damage the computers. Many computer rooms are also secure areas with limited access so it makes sense to have the equipment exterior to the room for service and regular maintenance.