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11. BACKUP OPERATIONS
(EMERGENCY OPERATION)
When a trouble occurred at an outdoor unit or at one of the compressors in outdoor unit, the troubled unit or
troubled compressor stops and a backup operation (emergency operation) is available by other outdoor units
and the compressors. Set up a backup operation following to the procedure below.
11-1. Before Backup Operation
Method of the backup operation differs by the contents of the trouble. Refer to the following table.
Trouble contents
When a trouble occurred on one of the compres-
sors in the same unit (Note 1)
When troubles occurred on the both compres-
sors in the same unit
Trouble of compressor coil
(Such as defect of compressor coil)
When a trouble occurred on refrigerating system
parts, fan system parts, or electric system parts
When a trouble occurred on temperature sensor
or pressure sensor
Backup operation method
Compressor backup
Outdoor unit backup or outdoor unit
backup during cooling season (Note 2)
Setup procedure
To item 2
To item 3 or item 4
(Note 1)
When a trouble of compressor coil, etc occurred,
deterioration of the oil is heavy.
Therefore do not perform a backup operation; otherwise a trouble of the other outdoor units may be caused.
(Note 2)
The outdoor unit to be processed with a backup operation should be restricted to one unit in the system
of 1
system
.
11-2. Compressor Backup Setup
<Outline>
When a trouble occurred on one of the two compressors, follow the procedure below if it is necessary to per-
form a backup operation by the other normal compressor.
<Work procedure>
1. Turn off the main power supplies of all the units connected to the system.
2. Set up the switch SW06 on the interface P.C. board of the outdoor unit with failure compressor as shown
below.
3. Turn on the main power supplies of all the units connected to the system.
Then setup operation for the compressor backup finishes.
Initial setup at shipment from factory
No.1 compressor (Left side) is defective.
No.2 compressor (Right front side) is defective.
SW06
Bit 1
Bit 2
Bit 3
Bit 4
OFF
OFF
OFF
OFF
ON
OFF
OFF
OFF
OFF
ON
OFF
OFF
Summary of Contents for MMC-AP0151H
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