User manual

Chapter 2 Environmental and Electrical Specifications 2-3
Air conditioning facilities usually do not provide functions to precisely monitor and
control the temperature and humidity throughout an entire computer room.
Generally, computer room air conditioning controls the temperature and humidity
according to the monitoring data at individual points corresponding to multiple
exhaust vents in the main unit and other units in the room. However, since air
conditioning facilities for underfloor ventilation perform such control according to
the monitoring data at each point close to an exhaust vent, the distribution of the
temperature and humidity across the entire computer room is uneven.
TABLE 2-2 lists the recommended temperature and humidity values for computer
rooms.
TABLE 2-2 Recommended Temperature and Humidity Values for Computer Rooms
Air conditioning
method
Point close to underfloor exhaust vent Monitoring and control point in room Remarks
Temperature Humidity % Temperature Humidity %
˚C ˚F ˚C ˚F
Direct
blowing or
duct blowing
- - - 24 ±2 75 ±4 45 ±5 -
Underfloor
ventilation
18 ±1 64 ±2 65 ±5 Target
temperature
of 24
˚C
Target
temperature
of 75
˚F
About
45% at
24
˚C
The room
temperature
and humidity
fluctuate,
without
control,
according to
the thermal
load in the
room.
Direct
blowing or
using duct
blowing and
underfloor
ventilation
together
18 ±1 64 ±2 65 ±5 24 ±2 75 ±4 45 ±5 -