Troubleshooting - Mitsubishi Electric MSZ-A09NA Service Manual

7-3. AUTO RESTART FUNCTION
When the indoor unit is controlled with the remote controller, the operation mode, the set temperature, and the fan speed
are memorized by the indoor electronic control P.C. board. The "AUTO RESTART FUNCTION" sets to work the moment
power has restored after power failure. Then, the unit will restart automatically.
Operation
If the main power has been cut, the operation settings remain.
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.)
How to release "AUTO RESTART FUNCTION"
Turn OFF the main power of the unit.
Solder the Jumper wire JR07 on the indoor electronic control P.C. board. (Refer to 8-7.)
MSZ-A09/12/15/17NA
MSY-A15/17NA
JR07
BZ
NOTE:
•
The operation settings are memorized when 10 seconds have passed after the indoor unit was operated with the
remote controller.
•
If 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 appliance 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.
8

TROUBLESHOOTING

MSZ-A09NA MSZ-A12NA MSZ-A15NA MSZ-A17NA MSZ-A24NA MSY-A15NA
MSY-A17NA MSY-A24NA MSZ-GA24NA MSY-GA24NA
8-1. CAUTIONS ON TROUBLESHOOTING
1. Before troubleshooting, check the following
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for miswiring.
2. Take care of the following during servicing
1) Before servicing the air conditioner, be sure to turn OFF the unit first with the remote controller, and then after confirm-
ing the horizontal vane is closed, turn OFF the breaker and/or disconnect the power plug.
2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the electronic
control P.C. board.
3) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
4) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
Lead wiring Housing point
11
MSZ-A24NA MSY-A24NA
MSZ-GA24NA MSY-GA24NA
CN152
JR07
BZ