Hitachi air conditioner error codes

The functional filling of Hitachi air conditioners can not only inform about the presence of a breakdown, but also diagnose the type of this breakdown and output the error code on an indicator of an inner unit or external unit. Our table presented below will help to decipher its error codes.

Hitachi RAS-H(V)RNME-AF air conditioner troubleshooting

RAS-H(V)RNME-AF is a model of air conditioner produced by the Japanese company Hitachi. Some of the optional functions of this model include anti-legionella (disinfection option), a swimming pool configuration, a summer switch-off function (that can be set to auto mode, if desired), and a tariff function (it can be enabled or disabled depending on your personal needs).

Alarm codeOriginDetail of abnormalityMain cause
2OutdoorActivation of outdoor unit protection device (Except for Alarm Codes 41,42)High pressure interrupting device activated
3OutdoorTransmission errorOutdoor fuse meltdown, indoor/outdoor connection wiring (breaking, wiring error, etc.)
4OutdoorInverter transmission abnormalityControl PCB - Inverter PCB connection wiring (breaking, wiring error, etc.)
5OutdoorPower phase detection abnormalityPower source wiring open phase in indoor units
6OutdoorUndervoltage, overvoltageOutdoor PCB abnormality, inverter PCB abnormality. DM, CB abnormality
7OutdoorAbnormal decrease of discharge gas superheat degreeExcessive refrigerant, expansion valve open-locked, fan motor locked
8IndoorCompressor-top Temperature over-increaseShortage or leakage of refrigerant, piping clogging, fan motor locked
11IndoorWater inlet thermistor abnormalityLoose, disconnected, broken or short-circuited connector
12IndoorWater outlet thermistor abnormalityLoose, disconnected, broken or short-circuited connector
13IndoorIndoor liquid pipe temperature thermistor abnor- malityLoose, disconnected, broken or short-circuited connector
14IndoorIndoor gas pipe temperature thermistor abnor- malityLoose, disconnected, broken or short-circuited connector
15IndoorWater outlet C2 thermistor abnormalityLoose, disconnected, broken or short-circuited connector
16IndoorWater DHWT thermistor abnormalityLoose, disconnected, broken or short-circuited connector
17IndoorAuxiliary thermistor abnormalityLoose, disconnected, broken or short-circuited connector
18IndoorWater outlet boiler thermistor abnormalityLoose, disconnected, broken or short-circuited connector
19OutdoorWater outlet HP thermistor abnormalityLoose, disconnected, broken or short-circuited connector
20OutdoorCompressor-Top temperature thermistor abnor- malityLoose, disconnected, broken or short-circuited connector
22OutdoorOutdoor temperature thermistor abnormalityLoose, disconnected, broken or short-circuited connector
24OutdoorOutdoor heat exchanger liquid pipe thermistor abnormalityLoose, disconnected, broken or short-circuited connector
31OutdoorIndoor/Outdoor combination setting errorOutdoor/Indoor unit capacity setting error, indoor total capacity excessively large/small
35OutdoorIndoor unit number setting errorIndoor units with the same number in a refrigerant piping system
38OutdoorOutdoor protection detection circuit abnormality Cooling overloadOutdoor PCB abnormality, error in wiring to outdoor PCB
41OutdoorHeating overloadOutdoor heat exchanger clogging/short circuit, broken outdoor fan motor
42 47OutdoorSuction pressure decrease prevention activated Inverter current sensor abnormalityOutdoor heat exchanger clogging/short circuit, expansion valve close-locked
51OutdoorShortage or leakage of refrigerant, piping clogging, expansion valve close-locked, fan motor locked Error in CT wiring, outdoor PCB abnormality, inverter PCB abnormality
48OutdoorOverload operation protection activation Inverter module errorCycle abnormality, inverter PCB abnormality, DM abnor- mality. heat exchanger clogging, etc.
53OutdoorCompressor. ISPM abnormality, heat exchanger clogging, etc.
54OutdoorInverter fin temperature abnormality Inverter non-operationFin thermistor abnormality, heat exchanger dogging, fan motor abnormality
55 59 b1OutdoorInverter fin temperature thermistor abnormality Error in address/refrigerant system settingInverter not operating or broken
EEOutdoorCompressor factor alarmLoose, disconnected, broken or short-circuited connector
70OutdoorHydraulic alarmAddress/refrigerant system setting over 64
71IndoorWater pump feedbackAlarm to notify damage to compressor occurs 3 times within 6 hours
72IndoorThermostat heater alarmWater pressure or water flow is not detected in the hydraulic cycle
73IndoorMixing overheating limit protection for mixed circuit.High temperature is detected in electric heater T>75°C Circuit 2 supply temperature > target temperature + offset
74IndoorUnit overheating limit protectionTwo > Tmax +5K
75IndoorFreeze protection by cold water inlet, outlet temperature detectionTl or Tg < -20°C for 30 seconds (Only heating mode)
76IndoorFreeze protection stop by indoor liquid tempera- ture thermistor
77IndoorOpentherm communication failureNo Opentherm communication for a continuous period of 1 minute.
78RF Communication failure Unit capacity setting errorNo communication for 1 hour with one or two RF recei- vers which are bound to the RF-Bridge.
79Indoor-outdoorLCD H-link transmission errorNo concordance between indoor and outdoor unit capa- dties
80Indoor-outdoor LCDNo H-link communication for a continuous period of 1 mi- nute between indoor and LCD user control by connection wiring (breaking, wiring error, etc.)

Hitachi RCI-1.0FSN3 air conditioner error codes

Hitachi RCI-1.0FSN3 is a high efficiency 4-way cassette air conditioner. It boasts good energy saving qualities, compact size and light weight. The cassettes are equipped with a built-in monitor sensor that is capable of reducing energy consumption. In addition to this the sensor serves for adjusting direction of airflow depending on your wish and individual preferences.

Code numberCategoryAbnormalityCause
1Indoor unitActivation of the safety deviceFailure of fan motor, drain discharge. PCB, relay, float switch activated
2Outdoor unitActivation of the safety deviceFailure of fan motor, drain discharge. PCB, relay, float switch activated
3Abnormal transmission between outdoor and indoor unitsIncorrect wiring, failure of PCB, tripping of fuse, power supply OFF
4TransmissionAbnormal transmission between inverter PCB (DIP-IPM) and outdoor unit PCB (PCB1)Abnormal transmission between PCB
5Power supplyAbnormal operation of picking up phase signalMain power supply phase is reversely connected or one phase is not connected.
6VoltageExcessively low voltage or excessively high voltage for the inverterIncorrect wiring or insufficient capacity of power supply wiring
7CycleDecrease in discharge gas superheatDischarge gas superheat less than 10 degrees is maintai- ned for 30 minutes.
8Excessively high discharge gas temperature at the top of compressorTemperature of top compressor: Td Td > 132°C over 10 minutes, or Td >140°C over 5 minutes
11Air inlet thermistor
12Sensor on indoor unitAir outlet thermistor Freeze protection thermistorFailure of thermistor, sensor, connection.
14Gas piping thermistor
16Remote thermistorFailure of thermistor
17Sensor on indoor unitThermistor of RCSFailure of thermistor
19Activation of the protection device for the indoor fan motorFailure of fan motor
20Compressor thermistorFailure of thermistor, sensor, connection.
21High pressure sensorIncorrect wiring, disconnected wiring, broken cable, short circuit.
22Sensor on outdoor unitThermistor for outdoor ambient temperature (THM7)Failure of thermistor, sensor, connection.
23Thermistor for discharge gas temperature (THM9)Incorrect wiring, disconnected wiring, broken cable, short circuit.
24Thermistor for evaporating temperature (THM8)Failure of thermistor, sensor, connection.
29Low pressure sensorIncorrect wiring, disconnected wiring, broken cable, short circuit.
31Incorrect capacity setting or combined capa- city between outdoor and indoor unitsIncorrect setting of the capacity code.
35SystemIncorrect indoor unit number settingDuplication of indoor unit number, number of indoor units over specifications.
36Incorrect indoor unit combinationR22 indoor unit
38Abnormality of picking up circuit for protec- tion (Outdoor unit)Failure of indoor unit PCB, incorrect wiring, connection to PCB in indoor unit.
41Cooling overload (possible activation of high pressure device)O.U. pipe thermistor temp, is higher than 55 °C and the compressor top temp, is higher than 95 °C, O.U. protection device is activated.
42Heating overload (high-pressure device may be activated)If I.U. freeze protection thermistor temp, is higher than 55 °C and compressor top temp, is higher than 95 °C, O.U. protection device is activated.
43PressureActivation of the safety device from com- pression ratio decreaseAbnormal compress (Compressor. Inverter damage)
44Activation of the safety device from excessi- vely high suction pressureOverload during cooling, high temperature with heating, loked expansion valve
45Activation of the safety device from excessi- vely high discharge pressureOverload (obstruction of HEX, short circuit) mixture of inert gas
47Activation of the safety device from exces- sively low suction pressure (protection from vacuum operation)Shortage or leakage of refrigerant, piping clogging, expan- sion valve close-locked, fan motor locked.
48Abnormality of current sensor for inverterFailure of DIP-IPM, heat exchanger clogged, locked com- pressor, EVI/EVO failure or overcharge.
51Abnormality of Current Sensor for InverterFailure of control PCB, inverter module.
53InverterProtection activation of inverter moduleInverter module abnormality.
Failure of compressor, clogging of heat exchanger.
54Inverter fin temperature increaseAbnormal inverter fin thermistor, clogging of heat exchan- ger, abnormal outdoor fan.
55Inverter Module abnormalityFailure of inverter module.
57Outdoor fanFan Motor abnormalityDisconnected wire of incorrect wiring between control PCB and inverter PCB.
Incorrect wiring or fan motor abnormality.
b1Indoor unit number settingIncorrect setting of the unit and the refrige- rant cycle number.Over 64 indoor units setting by number or indoor unit address.
b5Incorrect indoor unit connection number settingThere are more than 17 units not corresponding to H-Link II connected to one system
EECompressorCompressor protectionFailure of compressor.

Error codes and troubleshooting