Hitachi UTOPIA RAS-4HVRP2E - Page 268

10 Troubleshooting
Troubleshooting procedure
SMGB0136 rev.0 - 07/2021
266
Alarm code
04
Abnormal Communication between Inverter PCB and the Outdoor Unit PCB
• Thealarmcodeisashedonthe7-segmentdisplayoftheoutdoorunit.
• The alarm code is displayed on the wired controller of the indoor unit.
This alarm code is displayed after the operation is stopped when an abnormal communication occurs between the
inverter PCB (Driver Board) and the outdoor unit PCB (Main Board).
Phenomenon
Cause
Check Item
Action (Turn OFF
Main Switch)
Abnormal
communication between
inverter PCB and
outdoor unit PCB
Incorrect setting of DSW1 DIP3 of
outdoor unit board or driver board
(4~6HP)
The outdoor unit board or
driver board (4~6HP) has been
damaged
Is DSW1 DIP3 OFF?
Re-power ON to check if
the cause is eliminated
Switch DIP3 of DSW1 to OFF and
re-power ON
Replace the outdoor unit board or
driver board (4~6HP) if faulty