Service manual

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9-4. AUTO RESTART FUNCTION
When the indoor unit is operated with the remote controller, the signals of the operation mode, the set temperature,
and the fan speed are sent from the indoor electronic control P.C. board and memorized in the auto restart assembly.
When the main power is turned off and then turned back on, the unit restarts automatically in the memorized set
conditions approximately after 3 minutes.
NOTE:
•The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the remote
controller.
•If the main power is turned off or a power failure occurs while AUTO START/STOP timer is active, the timer setting is
cancelled.
•If the unit has been off with the remote controller before power failure, the auto restart function does not work as the
power button of the remote controller is off.
•To prevent breaker off due to the rush of starting current, systematize other home appliances not to turn on at the same time.
•When some air conditioners are connected to the same supply system, if they are operated before power failure, the
starting current of all the compressors may flow simultaneously at restart.
Therefore, the special counter-measures are required to prevent the main voltage-drop or the rush of the starting current
by adding to the system that allows the units to start one by one.
How to release “AUTO RESTART FUNCTION”
1 Turn off the main power for the unit.
2 Pull out the indoor electronic control P.C. board and the display P.C.board. (Refer to page 61 or 64.)
3 <MSZ09UN>
Solder the Jumper wire or the Resistor 220Ω to the JR07 on the indoor electronic control P.C.board.
(Refer to page 56.)
<MSZ12UN>
Disconnect the AUTO RESTART ASSY from CN104, and solder the Jumper wire to JHA on the indoor electronic control
P.C. board.(Refer to page 57.)
Operation
1 If the main power (115V AC) has been cut, the operation settings remain.
2 After the power is restored, the unit restarts automatically according to the memory.(However, it takes at least 3 minutes
for the compressor to start running.)
C111
CN201
C11
CN211
IC152
CN151
SW1
CN112
CN121
IC101
CN111
JR07
MSZ09UN
CN104
JHA
CN102
CN112
CN113
CN151
CN101
BZ
SW
IC101
RA102
CN201
MSZ12UN
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