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0920 IH-8771
5.
Up (+) and Down (–) Arrow Buttons
– These raise
or lower desired set temperature. When changing
set point, pressing the + or – key, the word SET will
appear on the display and the current set point
flashes ON and OFF. The value of the set point
is changed 1º each time + or – is pressed. The
adjusted set point flashes on and off 12 times after
the last change and then returns to display room
temperature.
NOTE: Lowering or raising the set point will
not change the supply air's temperature. For
best results, always adjust the set point to a
temperature the A/C unit can cycle on and off
at to avoid operational issues, such as freezing
or rapid discharge fan cycling. The A/C unit is
designed to maintain the set point when sized
properly. Constant operation without achieving
the set point may shorten the expected
operational life of the system.
NOTE: The lowest set point temperature
available for the A/C unit is 60º F, and the
highest setting is 95º F. The control will not
allow adjustments beyond these ranges.
SYSTEM OPERATION
1.
Turn on the A/C system
– Pressing the ON/OFF button
once on control panel will put unit in ON position.
ON will show on the right side of display as well as
the previously chosen mode.
2.
Cool
– If unit was previously set to cooling mode,
COOL will display. If compressor is running, COOL
will flash on the display. This will likely happen if unit
has been sitting for over two minutes, unless set point
is lower than the current room temperature. In this
case, unit is ready to automatically turn on once
the temperature rises above the set point. If the unit
was recently turned off or the unit turned itself off
because it reached the set point, the compressor will
not turn on until the system waits for approximately
two minutes. This prevents the compressor from being
damaged due to a condition called short cycling. F
(or C) will flash when unit is in timeout condition. When
the compressor starts, the F will stop flashing and
COOL will begin flashing.
NOTE: Condenser fan will not start immediately
with the compressor. If the display flashes 99,
this indicates ambient temperature of 99º F or
more. This is normal and will stop flashing when
the ambient temperature falls below 99º F.
3.
FAN
– If the unit was previously set to fan mode,
FAN will display and fan will start to run.
BUILT-IN SAFEGUARDS
TIME DELAY
This protects A/C unit from potential damage by
delaying the compressor from starting before the
pressures in the mechanical system equalize. This
always activates when A/C unit cycles off, is turned off,
power is lost and then restored or the operational mode
is changed. Display flashes F or C if the time delay is
activated.
HIGH-PRESSURE SWITCH AND ALARM
This protects A/C unit from potential damage to the
mechanical system by shutting down, sounding an
alarm and displaying a fault code (AL) when the system
pressure exceeds safe operating conditions. The high
pressure switch is a manual reset switch located in the
condenser inlet on the back of the system and labeled
HP Reset; it must be reset after the switch is activated
and the condition causing the trip is corrected.
AUTOMATIC RESTART
In the event of a power loss, A/C unit will resume
operation when the power is restored. All operational
functions are preserved in the memory of the
microprocessor board, including the ON/OFF selection.
CONDENSATE TANK AND HIGH-LEVEL ALARM
All A/C units come standard with an internal condensate
tank. Tank is equipped with an overflow safety cut-off.
When tank is full, the safety will automatically shut down
unit, sound an alarm and display a fault code (CF). This
prevents accidental flooding of the conditioned space.
To continue operation, empty water tank.
SERVICE PORTS
Service ports are located in filter access compartment
in the front of A/C unit below control panel. These
give service personnel a connection point for service
gauges to monitor the operating pressures of A/C unit
refrigeration system.
APPLICATION REQUIREMENTS
AIR TEMPERATURE
The environmental requirements of the A/C unit at the
installation site are 60-110º F for the condenser make-up
air located on the back of the unit. If unit is operated in
an environment above 110º F, the high pressure switch
may trip, stopping the unit’s compressor.
OPERATION CONTINUED
