Backup Operation - Panasonic U-10MF1E8 Service Manual

4. Backup Operation

This system includes an emergency automatic backup function that allows the A/C to operate during the period
after trouble occurs until repairs are made. However, during repair and at other times, use manual backup
operation.
4-1. Automatic Backup
For details, refer to the control functions section.
After the alarm details are sent to the control device, control for automatic backup operation begins when the
ON/OFF button of the wired remote controller is pressed again (operation is started after the alarm is cleared).
During this operating mode, "CHECK" flashes on the wired remote controller only to inform the user that operation
is in backup mode. However this is not displayed on any other control devices.
• In order to cancel automatic backup mode, it is necessary to reset the power on the control PCB of the outdoor
unit where the outdoor unit No. setting (S007) on the control PCB is set to No. 1 (main unit).
2
CAUTION
Backup operation is intended as emergency operation until repairs are made. Have repairs made as soon as
possible.
4-2. Manual Backup
This backup operation is the conventional method of backup operation. It involves disconnecting the failed outdoor
unit from the system, and operating only the normal outdoor units.
4-2-1. Backup operation by disconnecting the outdoor unit
(1) Changing the outdoor unit control PCB settings
< If the failed outdoor unit is not the No. 1 unit>
• Settings at No. 1 unit (main unit)
Switch on outdoor unit control PCB
System address (S003, S002)
No. of indoor units (S005, S004)
No. of outdoor units (S006)
Outdoor unit No. (S007)
• Settings at normal outdoor units other than the No. 1 unit
No particular changes
• Settings at the failed outdoor unit
No particular changes
However, close all service valves (suction tube, discharge tube, liquid tube, balance tube) at the failed outdoor
unit, and disconnect the wiring between the outdoor units.
If the power is not reset on the control PCB of the No. 1 outdoor unit (main unit),
backup mode operation will continue after the repairs are completed.
No change
No change
Subtract the number of failed units from the current setting.
No change
Outdoor Unit Repair Procedures
Action
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3-WAY SYSTEM