Hitachi FSG Series Service Manual page 53

Alarm Code
31
n "RUN" light flickers and "ALARM" is indicated on the remote control switch.
n The unit No., alarm code and the unit code is alternately indicated on the set temperature section, and the
unit No. and alarm code are indicated on the display of the outdoor unit PCB.
‘
This alarm code is indicated when the capacity setting dip switch, DSW2 on the outdoor unit PCB1, is not
set (all the settings from #1 to #3 are OFF) or mis setting.
‘
This alarm code is indicated when the total indoor unit capacity is smaller than 50% or greater than 150% of
the combined outdoor unit capacity.
Are #1-#3 of DSW2 on the
outdoor unit PCB1 set correctly?
Yes
Are #1-#4 of DSW3 on the indoor
unit PCB set correctly?
Yes
Are the setting of DSW1 on the
outdoor unit PCB1 and the setting of
DSW5 on the indoor unit PCB totally
same in a refrigerant cycle?
Yes
Total capacity of the indoor units is
wrong.
Phenomenon
Incorrect Capacity Setting of Indoor Unit
Incorrect Capacity Setting of Outdoor Unit
Total Indoor Unit Capacity Connected to the Outdoor
Unit is Beyond Permissible Range
Refrigeration Cycle Setting of Outdoor Unit and Indoor
Unit is Different.
Combination
Outdoor Unit Model
RAS-5FSG, RAS-5FS3
RAS-8FSG, RAS-8FS3
RAS-10FSG, RAS-10FS3
RAS-16FSG, RAS-16FS3
RAS-20FSG, RAS-20FS3
Incorrect Capacity Setting or Combined Capacity
between Indoor Units and Outdoor Unit
No
No
No
Cause
Combined Indoor Unit
Total Quantity Total Capacity (HP)
2-8 sets *1) 2.5-6.5
4.0-10.4
2-12 sets
5.0-13.0
2-13(16) sets *2) 8.0-20.8
2-16 sets 10.0-26.0
TROUBLESHOOTING
Check Item
Check combination of
indoor units and capacity
setting on PCB.
Check capacity setting on
outdoor unit PCB.
Check outdoor unit model
by calculating total indoor
units capacity.
Check refrigeration cycle
setting on outdoor unit
PCB and indoor unit PCB.
*1): If the capacity of one indoor unit is the same as of
the outdoor unit, the system can be operated.
*2): In case of changing the indoor unit capacity from
1.0HP or 1.5HP to 1.3HP by dip switch setting.
1
45
Set the capacity for PCB1.
Set the capacity for PCB.
Set them correctly
Action
(Turn OFF main switch)
Correctly set dip switch,
DSW3.
Correctly set dip switch,
DSW2.
Ensure that total indoor
unit capacity is from 50%
to 130%.
Set them correctly.
Notes