Carrier 38AN - Manual (Page 15)

COOLINO - DIRECT
LOUVERS SO AIR
BLOWS DOWN
(VERTICAL
DISCHARGE)
tDesirable range.
NOTE: Unit is equippect with manuai air vents which direct the air
from side to side. Up and down louver motion can be selected using
the remote controller. For maximum comfort, set louvers within the
swing range. See Adjusting Airflow section on page 14 for more
information.
Fig. 15 — Louver Adjustments
Operating Fault Diagnosis — The system includes
an automatic diagnosis feature which is activated under dif­
ficult or unacceptable operating conditions. If such condi­
tions occur, the system stops automatically, the operating fault
signal appears (green “UNIT ON” light on the front of the
fan coil unit flashes), and an analysis of the system operat­
ing conditions is initiated. The system will then be restarted
automatically, as soon as normal conditions have been re­
stored, or it will remain off. If the system does not start again,
the green “UNIT ON” light will flash an error code.
Microprocessor Control Operation — This sys­
tem is controlled by a microprocessor designed to give op­
timum levels of comfort and operating efficiency. The con­
trol is located in the 40QN unit. To operate the unit, the factory-
supplied remote controller is required.
There are 9 (QNB systems) or 12 (QNE/H systems) op­
erating modes (including the off mode) for the unit. Each
mode operates as follows:
• Off Mode — When the unit is in the Off mode, all func­
tions (compressor, outdoor fan, indoor fan, and air sweep)
are off, except the reversing valve (QNE/H only), which
will stay deenergized if the unit was last operated in the
Cooling mode.
• Air Circulation Mode (Fan Operation Only) —- When Air
Circulation mode is selected, the indoor fan will operate
continuously in the selected speed (high, medium, low, or
auto.). If the Auto, mode is selected, the indoor fan will
operate at low speed. The compressor and outdoor fan are
off. The reversing valve (QNE/H only) will remain in the
last operating mode.
• Cooling Mode — When the Cooling mode is selected, the
indoor fan will operate continuously at the selected speed
if the speed is high, medium, or low. If the indoor fan is
in Auto, mode, the fan will change operating speeds de­
pending on the difference between the room temperature
and the set point. The reversing valve (QNE/H only) will
be energized. The compressor cannot run for 3 minutes
from the time the system starts up or for 3 minutes from
the time the compressor last operated. When the tempera­
ture of the room is equal to or greater than the selected
temperature, the compressor and outdoor fan will operate
until the room temperature is 2° F below the set point, and
then shut off. When the room temperature is less than the
selected temperature, the compressor and outdoor fan re­
main off.
• Maximum Dehumidification Mode — When the Dehu­
midification mode is selected, the indoor fan will operate
continuously at the selected speed if the speed is high, me­
dium, or low. If the indoor fan is in Auto, mode, the fan
will change operating speeds depending on the room tem­
perature, If the room temperature is below the set point,
the indoor fan will run at ultra-low speed, and the com­
pressor could run for up to 4 minutes. (Ultra-low speed is
a control-driven speed [not user configurable] used to sample
the space when the fan would normally be off.) The re­
versing valve (QNE/H only) will be energized. The com­
pressor cannot run for 3 minutes from the time the system
starts up or for 3 minutes from the time the compressor
last operated.
Initial Operation — When the mode is first selected, one of
the following occurs:
1. If the room temperature is above or equal to the selected
temperature, the unit will operate for 16 minutes, and the
compressor and outdoor fan will operate. The indoor fan
will operate as in the Cooling mode. After 16 minutes of
operation (or when the room reaches 2° F below set point),
the unit switches to normal dehumidification operation.
2. If the room temperature is below the selected tempera­
ture, the unit will operate for 8 minutes as follows: the
compressor and outdoor fan will operate for 3 minutes.
The indoor fan will operate in low speed, and 30 seconds
after the compressor stops, the indoor fan stops. The unit
remains off for 1 minute, and then the indoor fan starts in
ultra-low speed for 30 seconds. The unit then switches to
normal dehumidification operation.
Normal Operation — One of the following will take place:
1. When the temperature of the room is equal to or greater
than the selected temperature (by not more than 3° F), the
unit will operate for 8 minutes as follows: the compres­
sor and outdoor fan will operate for 3 minutes. The in­
door fan will operate in low speed, and 30 seconds after
the compressor stops, the indoor fan stops. The unit re­
mains off for 1 minute, and then the indoor fan starts in
ultra-low speed for 30 seconds. The normal dehumidifi­
cation operation is repeated for the newly sensed room
temperature.
2. If the room temperature is equal to or greater than the
selected temperamre, but not by more than between 4° F
and 6° F, the compressor and outdoor fan operate for
4 minutes. The indoor fan will run at ultra-low speed and
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