8-4 Conditions for the Installation of Computer-Room Air Conditioners
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Computer
Fan
Air conditioner
Air intake
Free-access
floor
Air discharge
(1) Outdoor Temperature and Humidity
Generally the values set for general air conditioners are used, although the value higher than the maxi-
mum outdoor temperature and humidity may be set for devices like computer-room air conditioners that
must keep the air temperature and humidity under predetermined levels.
(2) Indoor Temperature and Humidity
There is a wide range of conditions set by different computer manufacturers, and the conditions need to
be set in consultation with the manufacturers. The most basic conditions include keeping dew condensa-
tion and static electricity from forming. It is also necessary to keep the room free of dust to ensure a
smooth operation of the computer.
(3) Matching the Volume of Air Flow
It is possible to use the fan on the computer to cool the room. This controlling method requires a certain
volume of cold air in proportion to the amount of heat produced by the device. The inlet panel is located at
the bottom of the unit, and the exhaust pipe is located either on the ceiling, front and back, or on the side.
(4) Considering a Back-up Air Conditioning System
When the system is not allowed to stop at all, a back-up system is necessary.
There are several different options for a back-up as the following:
1
Installing two sets of air conditioning systems necessary for the computer.
2
Utilizing regular office air conditioners (for people)
3
Using one of the units as a back-up
1
is used infrequently due to high costs involved.
2
involves many technical problems such as the
difference between preset conditions for computer rooms and office rooms. In general,
3
is a preferred
method. If
3
is chosen, the unit method (package method) is more economical than the central method.
