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9 MICROPROCESSOR CONTROL
● Compressor and
outdoor fan : ON-
OFF
● Operation mode
change :COOL-
HEAT.
1.OUTLINE OF MICROPROCESSOR CONTROL
● OFF-ON switching.
● COOL/DRY-AUTO-HEAT selector switching.
● Thermostat setting.
● TIMER mode selector-switching and Timer
setting.
● HIGH-LOW fan speed switching.
● AUTO Vane selector (AIR DISCHARGE)
switching.
● TEST RUN switching.
● CHECK mode switching.
(Self diagnostic trouble shooting)
● Room temperature thermistor (RT1)
● Pipe temperature thermistor (RT2)
● Auto vane’s angle setting.
● Booster heater ON-OFF Control.
● Emergency stop.
● Compressor protection
device working
● Defrosting
START-STOP
● Fan speed control.
● Crankcase heater control
ON-OFF.
● Self diagnostic function
Independent Control of
Outdoor Unit
OUTPUT to indoor unit
INPUT from indoor unit
INPUT to remote controller
Remote controller board
● Processes and transmits
orders.
OUTPUT to remote controller
Indoor controller board
● Receives orders from remote controller and tem-
perature data from indoor unit.
● Processes orders and data.
● Controls indoor and outdoor operation.
● Self diagnostic function.
w System control operation.
w Emergency operation.
w Set by dip switch on indoor controller board.
OUTPUT to outdoor unit
Polar three-wire cable
12VDC
123
1
2
3
Indoor
unit
Outdoor unit
● Indication LCD lights.
ON/OFF TEMP
MODEL
SELECT
NOT AVAILABLE
SWING
CHECK
FAN
TEST
RUN
˚F
˚C
AMPMSTOP
START
AMPM
COOL
DRY
AUTO
FAN
HEAT
OC276-A-1.qxp 03.11.25 9:04 AM Page 24