Toshiba MMU-AP0091H Before Backup Operation, Compressor Backup Setup, Outline, Procedure, 188

11.BACKUP OPERATIONS (EMERGENCY OPERATION)

When a trouble occurs in an outdoor unit or in one of the compressors in an outdoor unit, the malfunctioning unit or compressor stops and a backup operation (emergency operation) is available through the other function- ing outdoor units and compressors. A backup operation can be set up following the procedure below.

11-1. Before Backup Operation

The method of the backup operation will differ depending on the type of trouble. Refer to the following table.

Trouble contents	Backup operation method	Setup procedure
When a trouble occurs on one of the compressors	Compressor backup	To item 2
in the same unit (Note 1)
When a trouble occurs on the both compressors
in the same unit
Trouble of the compressor coil
(Such as defect of compressor coil)	Outdoor unit backup or outdoor unit	To item 3 or item 4
When a trouble occurs on the refrigerating system	backup during cooling season (Note 2)
parts, fan system parts, or electric system parts
When a trouble occurs on the temperature sensor
or pressure sensor

(Note 1) When a trouble of the compressor coil etc has occurred, deterioration of the oil will be high. Therefore do not perform a backup operation, as other units within the system may be damaged.

(Note 2) Only one outdoor unit within a given system can be subjected to the backup procedure.

11-2. Compressor Backup Setup

Outline

When a trouble occurs on one of the two compressors, follow the procedure below. If it is necessary perform a backup operation on the other normal compressor.

Procedure

1.Turn off the main power supplies to all the units connected to the system.

2.As shown below set up the switch SW06 on the interface P.C. board on the outdoor unit on which the com- pressor has failed.

		SW06
	Bit 1	Bit 2	Bit 3	Bit 4
Initial setup at shipment from factory	OFF	OFF	OFF	OFF
No.1 compressor (Left side) is defective.	ON	OFF	OFF	OFF
No.2 compressor (Right front side) is defective.	OFF	ON	OFF	OFF

3. Turn on the main power supplies of all of the units connected to the system.

After the backup set up for the outdoor unit in cooling season is complete, check the system operates.

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