Panasonic U-20ME1E81, Service Manual

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2WAY SYSTEM
Control Functions-Outdoor Unit
1
12. Backup Operation
12. Backup Operation
This system includes a function for automatic backup operation.
An alarm is displayed on the remote controller to inform the user that a failure has occurred.
When the following alarm occurs, automatic backup operation is engaged.
Automatic backup operation is not engaged in cases of serious alarm such as communications alarms, etc.
A : When there is one outdoor unit in the system, only compressor that has sensor failure stops.
When there are multiple outdoor units in the system, only the outdoor unit which contains the problem
stops but the other outdoor units in the system operate normally.
B : When there is one outdoor unit in the system, the backup operation does not work.
When there are multiple outdoor units in the system, only the outdoor unit which contains the problem
stops but the other outdoor units in the system operate normally.
12-1. Automatic Backup Operation
12-1-1. Alarms That Result in Automatic Backup Operation
Alarm list 1 (Backup operation continues unless power supply of all outdoor units is turned off.)
Over-current of compressor 1
Compressor 1 CT sensor disconnected or short-circuit
Over-current of compressor 2
Lock current of compressor 2
HIC trouble for compressor 1
Over-current of inverter device
Outdoor unit fan motor trouble
Malfunction of compressor 1 start
A
A
A
A
A
A
A
A
A
B
Over-current of compressor 3
Lock current of compressor 3
Alarm display
H03
H01
H11
H31
H12
H21
H22
P16
P29
P22
2WAY SYSTEM
Control Functions-Outdoor Unit
NOTE:
After automatic backup operation caused by alarm listed in alarm list 1, it will not be canceled automatically
when the repair of the failed outdoor unit is completed.
Automatic backup mode will be canceled only when the power on all outdoor unit is reset.
Therefore, after repair work is completed, be sure to check whether or not automatic backup mode has been
canceled.
SM830204-05_2WAY SYS.indb 37 2015/01/21 17:00:05