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145
EMERGENCY OPERATION switch
E.O.
SW
Operation mode
COOL
HEAT
Set temperature
24
:
24
:
Fan speed
Medium
Medium
Horizontal vane
Auto
Auto
The operation mode is indicated by the Operation
Indicator lamp on the indoor unit as following
Operation indicator lamp
Press again <Heat>
Press once <Cool>
Press once again <Stop>
Not lighted
Lighted
11-9. EMERGENCY/TEST OPERATION
In case of test run operation or emergency operation, use EMERGENCY OPERATION switch on the front of the indoor
unit. Emergency operation is available when the remote controller is missing, has failed or the batteries of the remote
controller run down. The unit will start and AREA lamp will light.
The first 30 minutes of operation is the test run operation. This operation is for servicing. The Indoor fan speed runs at
High speed and the system is in continuous operation (The thermostat in ON).
After 30 minutes of test run operation, the system shifts to EMERGENCY COOL / HEAT MODE with a set temperature of
24°C. The fan speed shifts to Med.
The coil frost prevention works even in emergency operation, and defrosting too.
In the test run or emergency operation, the horizontal vane operates in VANE AUTO (
) mode.
Emergency operation continues until EMERGENCY OPERATION switch is pressed once or twice or the unit receives any
signal from the remote controller. In case of latter, normal operation will start.
NOTE : Do not press EMERGENCY OPERATION switch during normal operation.
11-10. INVERTER SYSTEM CONTROL
11-10-1. Inverter main power supply circuit
SYMBOL
IPM
CB1~3
CT1~2
CT61
L
PFC
R64A, R64B
X64
NAME
INTELLIGENT POWER MODULE
SMOOTHING CAPACITOR
CURRENT TRANSFORMER
CURRENT TRANSFORMER
REACTOR
POWER FACTOR CONTROLLER
CURRENT-LIMITING RESISTOR
RELAY
FUNCTION
It supplies three-phase AC power to compressor.
It stabilizes the DC voltage.
It measures the current of the compressor motor.
It measures the current of the main power supply circuit.
It rectifies AC, controls its voltage and improves the power factor of
power supply.
It restricts rush current with the resistance.
It short-circuits the resistance which restricts rush current during the
compressor operates.
Function of main parts
W
MC
V
U
W
V
U
IPM
CB3
CB2
+CB1
PFC
CT61
N/F
CT2
CT1
X64
R64A/R64B
L
POWER
SUPPLY
POWER BOARD
P. C. BOARD
FILTER
NOISE
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