Hitachi RAS-(2-6)HVNP1(E), Service Manual

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8 Troubleshooting
217
SMGB0087 rev.0 - 12/2013
8
8.2.2 Alarm codes for the outdoor and indoor units
• The RUN LED flickers and “ALARM” is displayed on the remote control switch.
• The unit number, the alarm code and the unit code are alternately displayed on the set temperature section.
• The unit number and the alarm code are displayed on the 7 segments of the outdoor unit PCB and Remote control
Screen (if installed).
Code
number
Category Type of abnormality Main cause
1 Indoor unit Activation of protection device (float switch)
Failure of fan motor, drain discharge, PCB, relay, float
switch activated (High Water Level in Drain Pan, Ab-
normality of Drain Pipe, Float Switch or Drain Pan)
2 Outdoor unit
Activation of protection device (high pressure
cut)
Activation of PSH, locked motor, abnormal operation
in the power supply phase. Failure of fan motor, drain
discharge, PCB, relay, float switch activated. (Pipe
Clogging, Excessive Refrigerant, Insert Gas Mixing,
Fan Motor Locking at Cooling Operation)
3
Transmission
Abnormal transmission between outdoor and
indoor units
Incorrect wiring. Loose terminals, Failure of PCB. Trip-
ping of fuse. Power supply OFF.
4
Abnormal transmission between inverter PCB
(DIP-IPM) and outdoor unit PCB (PCB1)
Transmission failure between inverter PCBs. (Loose
Connector, Wire Breaking, Blowout of Fuse)
5 Power supply
Reception of abnormal operation code for detec-
tion of power source phase
Power source with abnormal wave pattern. Main power
supply phase is reversely connected or one phase is
not connected. (units wiht power supply 3N~ 400V
50Hz only)
6 Voltage
Excessively low voltage or excessively high volt-
age for the inverter
Voltage drop in power supply. Incorrect wiring or insuf-
ficient capacity of power supply wiring.
7
Cycle
Decrease in discharge gas superheat
Excessive Refrigerant Charge, Failure of Thermistor,
Incorrect Wiring, Incorrect Piping Connection, Expan-
sion Valve Locking at Opened Position (Disconnected
Connector).
8
Excessively high discharge gas temperature at
the top of compressor
Insufficient refrigerant charge, refrigerant leakage.
Expansion valve closed or clogged.
11
Indoor units
sensor
Air inlet thermistor
Failure of thermistor, sensor, connection. (Incorrect
Wiring, Disconnected Wiring, Wire Breaking, Short
Circuit).
12 Air outlet thermistor
13 Freeze protection thermistor
14 Gas piping thermistor
16 Remote thermistor
17 Thermistor of RCS
19 Fan motor
Activation of the protection device for the indoor
fan motor
Failure of fan motor
20
Outdoor unit
sensor
Compressor thermistor
Incorrect wiring, disconnected wiring, broken cable,
short circuit.
21 High pressure sensor
22
Thermistor for outdoor ambient temperature
(THM7)
23
Thermistor for discharge gas temperature
(THM9)
24 Thermistor for evaporating temperature (THM8)
Incorrect Wiring, Disconnected Wiring, Wire Breaking,
Short Circuit, Fan Motor Locking at Heating Operation.
29 Low pressure sensor
Incorrect wiring, disconnected wiring, broken cable,
short circuit.