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1-11
TROUBLESHOOTING
1.1.4 Emergency Operation when Inverter Compressor is Damaged
(1) Failure of Inverter Compressor
a. Contents of Operation
(Applied Models: RAS-8FSG(3), 10FSG(3), 16FSG(3), 20FSG(3), 24FSG1(5), 30FSG1(5) /
RAS-8FXG(3), 10FXG(3))
* This operation is an emergency operation by a constant compressor, when the inverter
compressor is failed.
* By turning ON “#1” of DSW7 on PCB1 and “#1” of DSW1 on PCB3, emergency operation is
started. (In Case of 5 to 20HP)
* By turning ON “#6” of DSW4 on PCB1 and “#1” of DSW1 on ISPM, emergency operation is
started. (In Case of 24 and 30HP)
* Control of the emergency operation is same with normal control except the inverter compressor
stoppage.
b. Operating Condition
The constant speed compressor is forced to be stopped for compressor protection under the
condition below.
Total Capacity of Thermo-ON indoor units < 50% of Outdoor Unit Capacity
In case of the above condition, the compressor is operated and stopped repeatedly, and it may
cause the compressor failure. Therefore, the compressor is forced to be stopped to protect it.
NOTE:
If the printed circuit board for inverter (PCB3) is damaged, this is not available.
Setting airflow of indoor unit is keeping during enforced stoppage.
Therefore, it is recommended that setting airflow is “Lo” to avoid the person in the room feels cold.
c. Method of Emergency Operation
Checking Before Emergency Operation.
* Measure insulation resistance of the inverter compressor.
Do not perform the emergency operation when the insulation resistance is 0
Ω
.
There is a possibility that refrigerant oil may be oxidized, if the emergency operation is
performed, the other compressor is damaged.
* In case of total capacity of Thermo-ON indoor units are more than 50% of outdoor unit capacity,
emergency operation is available.
* In this emergency operation, frequency of the compressor is not controlled at each 1Hz.
Therefore, alarm code “07”, “43”, “44”, “45” or “47” may be indicated on LCD. Details of alarm
codes are shown in the alarm code table (page 1-23).
* This emergency operation does not provide sufficient cooling and heating capacity.
* This method is an emergency operation temporarily when the inverter compressor is damaged.
Therefore, change the new one as soon as possible.
* Turn OFF “#1” of DSW7 on PCB1 and “#1” of DSW1 on PCB3 after changing the new
compressor. (In Case of 5 to 20HP)
Turn OFF “#6” of DSW4 on PCB1 and “#1” of DSW1 on ISPM after changing the new
compressor. (In Case of 24 and 30HP)
If this setting is not performed, the inverter compressor will be damaged.
d. Emergency Operation
* Turn OFF all the power source switches.
* Disconnect the wiring from the inverter compressor. Insulate the faston terminals for inverter
compressor wires by insulation tape.
* Set the No.1 of DSW7 on the PCB1 and No.1 of DSW1 on the PCB3 at the “ON” side.
(In Case of 5 to 20HP)
Set “#6” of DSW4 on PCB1 and “#1” of DSW1 on ISPM at the “ON” side.
(In Case of 24 and 30HP)
* Turn ON all the power source switches.
* Operate the system by remote control switches.
* The system is stopped by turning OFF all the remote control switches or turning OFF all the
power source switches.