© 2013 Pentair Equipment Protection 87976428
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PRINCIPLES OF OPERATION
HIBOY® air conditioners are designed specifically to cool and dehumidify the internal environments of cabinets
and enclosure which are used to package electronic components, thus assuring a cool, clean atmosphere for
reasons of optimum performance and longevity.
Hot air inside the electronic enclosure or rack is removed and cooled by means of refrigeration. The hot air is
drained from the enclosure interior through the evaporator air return opening in the bottom middle of the air
conditioner. The air is drawn through the evaporator coil where it is cooled and discharged back to the enclosure
interior through two evaporator outlet openings in the bottom rear of the unit. Any moisture in this air condenses
on the evaporator coil and ultimately collects in the condensate tray where it is then discharged from the air
conditioner via the condensate drain tube.
The closed-loop design of the air conditioner assures that this clean, cooled air never mixes with the hot,
dirty ambient air that is used only for cooling the compressor and accomplish the heat exchange through the
condenser coil. Generally the cabinet or enclosure air which is being cooled and recirculated over and over again
does not require any filtering media.
Room or ambient air drawn into the air conditioner through the inlet filter, across the compressor and through
the condenser coil is usually dirty, dusty and/or humid air depending upon the specific environment in which the
air conditioner is required to operate. This ambient air is discharged by the condenser duplex blower back to the
ambient environment. The temperature of this discharged air will be quite warm or actually hot depending on the
ambient temperature and the work load imposed on the air conditioner.
Provided the inlet filter is properly maintained by frequent cleaning and/or replacement, the inlet filter will assure
relatively clean air to pass through the condenser coil. Dirty filters will hamper the optimum operating efficiency
of the air conditioner.
NOTE: The condenser filter will require periodic maintenance, see MAINTENANCE on page
9.
When the HIBOY® air conditioner is mounted in the enclosure or rack, it is recommended that an electrical
lockout or safety switch be installed to interrupt operation of the unit while the enclosure door is opened.
If electrical power is momentarily interrupted to the air conditioner and reapplied immediately (within 3 to 5
seconds)., the compressor may not restart due to the high back pressure of the compressor.
DO NOT attempt to restart the air conditioner for at least one minute after the unit has been
shut off either accidentally or intentionally.
It takes at least one minute after shut-down for the compressor suction and discharge pressure to equalize in
order to restart the air conditioner.
Operating the HIBOY® air conditioner at ambient temperatures below the minimum or above
maximum temperatures indicated on the nameplate will void all warranties.
It is recommended that the warranty section of this manual be read in order to familiarize
yourself with parameters of restricted operation.
It is very important to install the drain system in accordance with the installation instructions on page 7.
By elevating the drain tube above the exit point on the air conditioner, you will cause the collected condensate
or water to back up the drain tube and flood the condensate tray. This flooding or overflowing water could be
transmitted into the electronic cabinet or enclosure by the air exhausted from the evaporator blower, thus causing
damage to the expensive electronic components.
The moisture that the enclosure air can contain is limited. If moisture flows from the drain tube continuously, this
can only mean ambient air is entering the enclosure. Remember frequent opening of the enclosures door admits
humid air which the air conditioner must then dehumidify.
