Hitachi RAS-4-HNPE - Troubleshooting Using the 7 Segment Display

8. Troubleshooting
268
SMGB0079 rev.0 - 01/2013
8.3.3 Troubleshooting using the 7 segment display
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Simple checking by 7-segment display
1
Turn ON indoor unit connected to
the outdoor unit
During auto-addressing, the following items can be checked using the
outdoor unit’s on-board 7-segment LED display:
1 Disconnection of power supply to the indoor unit.
2 Reverse connection of the operating line between the outdoor and
indoor units.
3 Duplication of indoor unit number.
2 Turn ON the outdoor unit
3 Auto-addressing starts
Outdoor unit, circuit board, PCB1
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Checking method by 7-segment display
Operating conditions and each part of refrigeration cycle can be checked by 7-segment and push switches (PSW) on the
PCB in the outdoor unit. During checking data, do not touch the electric parts except for the indicated switches because
220-240V is applied to them. Pay attention not to contact the tools with electrical parts. If contacted, electrical parts will be
damaged.
8
8
Y52C
Y21
FAN1
YCH
PSH
FAN2
Y20F
Y20A
8.8.
SEG1 PSW1 PSW2 PSW3
Manual
defrost
• To start checking, press PSW2 switch for more than three se-
conds.
• To proceed checking, press the PSW2 switch.
• To back to the previous item, press the PSW3 switch.
• To cancel this checking, press the PSW2 switch for more than
3 seconds.