Hitachi UTOPIA R32 Series Technical Catalogue page 129

11 Troubleshooting
Alarm codes
Code Category
Incorrect capacity setting of outdoor unit
31
and indoor unit
Incorrect setting of other indoor unit
32
number (RPK series only)
35 System Incorrect indoor unit number setting
36 Incorrect of indoor unit combination
Abnormality of picking up circuit for
38
protection (outdoor unit)
3A Abnormal outdoor unit capacity
Incorrect setting of outdoor unit models
3b
combination or voltage
Outdoor Unit
Abnormal communication between main
3d
unit and sub unit(s)
Abnormal combination between inverter
3E
PCB and outdoor PCB
Activation of the protection device from
43
compression ratio decrease
Activation of the protection device from
44
excessively high suction pressure
Activation of the protection device from
45
Protection excessively high discharge pressure
Device
Activation of the protection device
47 from excessively low suction pressure
(protection from vacuum operation)
48 Abnormality of current sensor for inverter
Shortage of energy transfer at IDU and
49
ODU side
Outdoor Unit
Compressor continuously in operation
50
under very low discharge pressure
51 Sensor Abnormality of current sensor for inverter
53 Protection activation of inverter module
Inverter
54 Inverter fin temperature increase
55 Inverter Module abnormality
57 Activation of fan controller protection
Alarm for abnormality of fan or
88
compressor driver
Fan Controller
5A Abnormal fan controller fin temperature
5b Activation of overcurrent protection
5C Abnormality of fan controller sensor
A1 Indoor Unit Active filter abnormality detection
121 TCGB0136 rev.1 - 05/2021
Content of Abnormality Leading Cause
Incorrect capacity setting of outdoor unit and indoor unit,
excessive or insufficient indoor unit total capacity code
Problem with a different Indoor Unit in the same refrigerant
cycle; (Failure at the power supply, defective PCB)
Duplication of indoor unit number in same refrigerant cycle
number
Outdoor unit is R32 designed and there is at least one
indoor unti not supporting R32 refrigerant.
Failure of protection detecting device (incorrect wiring of
outdoor PCB)
Outdoor unit capacity > Permitted maximum
Incorrect setting of main and sub units(s) combination or
voltage
Incorrect wiring, disconnect wire, breaking wire, PCB failure
Incorrect combination between inverter PCB and outdoor
PCB
Abnormal compression (failure of compressor or inverter,
loose power supply connection)
Overload during cooling, high temperature with heating,
locked expansion valve
Overload (obstruction of Heat exchanger or clogging, short
circuit) mixture of inert gas
Shortage or leakage of refrigerant, piping clogging,
expansion valve close-locked, fan motor locked
Overload operation, compressor failure, failure of DIP-IPM,
heat exchanger clogged, locked compressor, EVI/EVO
failure or overcharge
Shortage of refrigerant due to gas leakage
Abnormality operation at a low ambient temperature
Current sensor failure
Driver IC error signal detection (inverter module abnormality,
protection for overcurrent, voltage decrease, short circuit),
instantaneous overcurrent. Failure of compressor, clogging
of heat exchanger
Abnormal inverter fin thermistor, clogging of heat exchanger,
abnormal outdoor fan.
Failure of inverter module (PCB failure)
Driver IC error signal detection (protection for overcurrent,
voltage decrease, short circuit), instantaneous overcurrent,
disconnected wire or incorrect wiring between control PCB
and inverter PCB, incorrect wiring or fan motor abnormality.
The fan or the compressor driver do not transfer an
identification code
Fin thermistor fault, heat exchanger clogging, fan motor fault
Fan motor failure
Failure of current sensor (instantaneous overcurrent,
increase of fin temperature, low voltage, grand fault, step-
out)
Active filter abnormality
11