Air Conditioner Filters - Fujitsu M10 Series Installation Planning Manual

(3) Humidifiers used with underfloor-ventilation air conditioners
Certain types of underfloor-ventilation air conditioners have a boiling humidifier and
a draft fan installed at adjacent locations such that drops of boiling water from the
humidifier can enter the draft fan for aerial dispersion. If this occurs, impurities in the
drops of water can adhere to the air inlet of the equipment as white powder or turn
into sandy particulate under the floor and cause corrosion.
Care should be taken in selecting or designing an air conditioner to prevent the
dispersion of drops of boiling water from a boiling humidifier. In scheduled facility
checkouts, check for white powder on the draft fan, sandy particulate under the floor,
and white powder on the air inlets of the equipment and any resultant corrosion to
ensure that the air conditioner is working correctly.
4.5.2

Air conditioner filters

Use filters that provide a high collection efficiency and that do not have any adverse
effects on the server system. Also install a filter at the outside air inlet to remove dust
from the outside air.
(1) Filter collection efficiency
Use of a filter with a collection efficiency of 95% or higher as measured by the
gravimetric method is recommended.
(2) Filter types
Filters must be mechanical ones made of a nonwoven cloth or similar material. Do not
use electrostatic dust collectors as they generate ozone gases, which could degrade
rubber parts.
C120-H007-08EN
4.5 Precautions Pertaining to the Installation of Air Conditioners
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