Hitachi UTOPIA RAS-4HVRP2E - Page 263

10 Troubleshooting
Troubleshooting procedure
SMGB0136 rev.0 - 07/2021
261
10
Code Category Content of Abnormality Leading Cause
18
Indoor Fan
Motor
Abnormality of Indoor Fan System
Abnormality of Indoor Fan Motor (Step-Out),
Indoor Fan Controller Failure
19
Activation of Protection Device for Indoor
Fan
Fan Motor Overheat, Lockup
1A
Indoor Fan
Controller
Abnormality of Fan Controller Fin
Temperature
Abnormality of Fin Thermistor or Fan Controller,
Heat Exchanger Clogging, Abnormality of Fan Motor
1b Activation of Overcurrent Protection Abnormality of Fan Motor
1C Problem with Current Sensor Abnormality of Fan Controller Current Sensor
1d Activation Fan Controller Protection Driver IC Error Signal Detection, Instantaneous Overcurrent
1E
Abnormality of Indoor Fan Controller
Voltage
IndoorVoltageDecrease,InsufcientCapacityof
Power Supply Wiring
20
Sensor on
Outdoor Unit
Abnormality of compressor thermistor
21 Abnormality of High Pressure Sensor
Incorrect Wiring, Disconnecting Wiring,
Breaking Wire, Short Circuit
22 Abnormality of Outdoor Air Thermistor
23
Abnormality of Discharge Gas Thermistor
on Top of Compressor
24
Abnormality of Heat Exchanger Liquid
Pipe Thermistor
25
Abnormality of Heat Exchanger Gas Pipe
Thermistor
29 Abnormality of Low Pressure Sensor
30
System
Incorrect DSW Settings of Outdoor Unit
for CH-Box
Connection of CH-Box to Heat Pump System, Disconnection
of CH-Box to Heat Recover System. CH-Unit (Generation 1
mode) and CH-BOx (Generation 2 model) are used in the
same system together.
31
Incorrect Capacity Setting of Outdoor Unit
and Indoor Unit
Incorrect Capacity Setting of Outdoor Unit and Indoor Unit,
ExcessiveorInsufcientIndoorUnitTotalCapacityCode
35 Incorrect Setting of Indoor Unit No.
Duplication of Indoor Unit Number In same Refrigerant
Cycle Number
36 Incorrect of Indoor Unit Combination
Alarm triggered in case Outdoor Unit es R32 and Indoor Unit
is not designed for R32.
38
Abnormality of Picking up Circuit for
Protection in Outdoor Unit
Failure of Protection Detecting Device (Incorrect Wiring of
Outdoor PCB)
Compressor thermoistat (clixon) is already activated when
compressor is OFF
3E Outdoor Unit
Abnormal Combination between Inverter
PCB and Outdoor PCB
Incorrect Combination between Inverter PCB and Outdoor
PCB
43
Protection
Device
Activation of Pressure Ratio Decrease
Protection
Defective Compression (Failure of Compressor or Inverter,
Loose Power Supply Connection)
44
Activation of Low Pressure Increase
Protection
Overload at Cooling, High Temperature at Heating,
Expansion Valve Locking at Open Position (Loose
Connector)
45
Activation of High Pressure Increase
Protection
Overload Operation (Heat Exchanger Clogging, Short Circuit
ofAirow),PipeClogging,ExcessiveRefrigerant,InertGas
Mixing
47
Activation of Low Pressure Decrease
Protection
InsufcientRefrigerant,PipingClogging,ExpansionValve
Locking at Close Position (Loosen Connector)
48
Activation of Inverter Overcurrent
Protection
Overload Operation, Compressor Failure
49
Outdoor Unit
Shortage of energy transfer at IDU and
ODU side
Shortage of refrigerant due to gas leakage
50
Compressor continuously in operation
under very low discharge pressure
Abnormality operation at a low ambient temperature
51 Sensor Abnormal Inverter Current Sensor Current Sensor Failure
53
Inverter
Inverter Error Signal Detection
Driver IC Error Signal Detection (Protection for Overcurrent,
Voltage Decrease, Short Circuit), Instantaneous Overcurrent
54 Abnormality of Inverter Fin Temperature
Abnormal Inverter Fin Thermistor,
Heat Exchanger Clogging, Fan Motor Failure
55 Inverter Failure Inverter PCB Failure