Perth's Hitachi fault code lookup

Hitachi fault codes decoded

86 codes covered — what each one means, the likely cause, and whether it's worth trying something yourself before booking. Compiled from Hitachi documentation.

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Hitachi uses two completely separate systems, and mixing them up is the most common lookup mistake: wall splits signal by counting flashes on the TIMER lamp and outdoor LED, while ducted and cassette systems on a wired controller use H-LINK alarm numbers. A bare two-digit number means nothing until you know which scheme it belongs to — the tables below are labelled accordingly.

Before you scroll: exact meanings can vary between model series — treat this as a well-informed starting point, not a service manual for your specific unit. And if a code appears alongside burning smells, breaker trips or water pouring from the unit, skip the table: switch off and call 0434 951 341.

How to find your Hitachi fault code

Wall splits — count the TIMER lamp

1 When a fault trips, the indoor unit's TIMER lamp flashes in a repeating count. Count the flashes between pauses.
2 2 flashes isn't a fault at all — it means the outdoor unit is in forced or test operation.
3 4 flashes means the fault is in the outdoor unit: the real detail is on the outdoor PCB's LED, which is a technician's job to read behind the service cover.

Multi-splits — the LD301 / LD302 sub-codes

1 On Multizone (multi-split) outdoor units only: when LD301 is lit continuously and LD302 blinks, the blink count identifies which thermistor has failed.
2 Count the LD302 blinks and read the table below — the numbering runs 1 to 9.
3 If LD301 and LD302 are lit together with LD303, that's an overload condition rather than an alarm.

Ducted and cassettes — wired-controller alarms

1 Systems on a wired controller (ducted, cassette, under-ceiling and light-commercial) use Hitachi's H-LINK alarm numbering, shown directly on the controller.
2 These two-digit alarm numbers are a completely different scheme from the wall-split lamp counts — check which system you're reading before looking a number up.

Worth knowing: Hitachi uses two unrelated numbering schemes: wall splits signal by TIMER-lamp and outdoor-LED flash counts, while wired-controller systems (ducted, cassette and light-commercial) use H-LINK alarm numbers. A bare two-digit number means nothing until you know which scheme it belongs to — the tables below are labelled accordingly. Meanings also shift between series (RAK-NH versus RAS-FH ranges differ on several lamp counts), so confirm against your model's manual.

Hitachi fault code tables

Try this first safe check before calling anyone Book a service needs a technician Switch off & call stop running the system

Wall split & multi-split — indoor unit TIMER lamp flash codes (wireless-remote models)

Code	What it means	Likely cause	What to do
TIMER lamp 1 flash (code 01)	Indoor coil too warm in cooling mode, or too cold in heating mode — the system isn't moving heat the way it should.	Hitachi's leading causes: a jammed or defective reversing (4-way) valve, a faulty reversing valve coil, or a disconnected/faulty coil thermistor.	Book a service
TIMER lamp 2 flashes (no code)	Outdoor unit is running in forced/test operation. This is NOT a fault.	A technician has left the outdoor unit in forced-run (test) mode, or the test switch on the outdoor PCB is still pressed in.	Try this first Switch the system off at the isolator/breaker for a full 2 minutes, then restore power. If the 2-flash pattern returns, the outdoor test switch is still engaged and needs a technician.
TIMER lamp 3 flashes (code 03)	Communication error between the indoor and outdoor unit — they have stopped talking to each other.	Interconnecting control cable fault, loose terminal, blown outdoor fuse, outdoor unit not powered, or an indoor/outdoor PCB failure. Often triggered by a brownout or a nearby lightning strike.	Try this first Turn the system off at the wall isolator or circuit breaker for a full 2 minutes, then power back on. A one-off comms dropout after a power interruption usually clears; if it returns immediately, book a technician (do not open any electrical covers).
TIMER lamp 4 flashes (code 04)	The fault is in the OUTDOOR unit. The indoor unit is only reporting it — the actual code must be read from the outdoor unit's PCB LED.	Any outdoor-side fault: compressor, inverter, fan motor, power supply or outdoor sensor. See the outdoor code group below.	Book a service
TIMER lamp 9 flashes (code 09)	Indoor room thermistor or heat-exchanger thermistor fault (Summit/Monozone/Multizone and RAK-NH ranges).	Failed or disconnected indoor thermistor. On RAS-FH series the same fault is 5 blinks and DC fan over-current is 6 blinks — always confirm against your model's manual.	Book a service
TIMER lamp 10 flashes (code 10)	Indoor fan motor over-current or abnormal rotation speed — the fan is not spinning at the commanded speed.	Failed or seized indoor fan motor, obstructed barrel fan, or an indoor PCB fan-drive failure.	Book a service
TIMER lamp 13 flashes (code 13)	EEPROM data error — data read from IC401 or IC402 on the indoor control PCB is incorrect.	Corrupted or failed memory on the indoor control PCB; the remedy is PCB replacement.	Book a service
TIMER lamp 6 flashes (code 06)	Abnormal drain water level — indoor float switch has activated and the unit has shut down	Blocked or kinked drain line, dirty drain pan, failed condensate pump/drain pump, or a faulty/stuck float switch. Applies to residential cassette and ducted indoor units (RAI/RAD/RPI style) rather than back-to-wall wall splits.	Try this first
TIMER lamp 7 flashes (code 07)	Drain pump forced (test) operation — the drain pump test switch on the indoor PCB has been left engaged	Service technician left the indoor PWB drain-pump test switch in the test position after commissioning or a drain clean-out; unit runs the pump continuously and flags the state.	Book a service
Outdoor LED 1 flash (01)	Reset stop — the outdoor microcomputer has reset itself	Power supply disturbance, brownout or momentary supply interruption. If the LED repeats a single flash frequently during normal running, the outdoor control PWB is failing.	Try this first

Wall split & multi-split — outdoor unit codes (TIMER lamp 4 flashes, then count the outdoor PCB LED)

Code	What it means	Likely cause	What to do
Outdoor LED 2 flashes (02)	Peak current cut — over-current detected on the compressor.	Locked/seized compressor, failed inverter power module (IPM/SPM) or outdoor PCB failure.	Switch off & call
Outdoor LED 3 flashes (03)	Compressor abnormal low-speed rotation / abnormal rotor position.	Failing compressor, faulty inverter power module or outdoor PCB.	Switch off & call
Outdoor LED 4 flashes (04)	Compressor switching failure — the inverter cannot commutate the compressor correctly.	Faulty inverter power module, compressor winding fault or outdoor PCB failure.	Switch off & call
Outdoor LED 5 flashes (05)	Overload lower-limit cut — the compressor was pulled down to its minimum speed under over-current, then stopped.	Outdoor coil clogged or airflow obstructed (in cooling), indoor airflow restricted or filters blocked (in heating), refrigerant overcharge, or supply voltage problems.	Try this first Turn the system off, then clear leaves, grass clippings, boxes or plant growth from around and above the outdoor unit (leave at least 300 mm clear on the coil faces and 1 m above), and wash out the indoor filters. Restart after 2 minutes. If it trips again, book a technician.
Outdoor LED 6 flashes (06)	OH (compressor discharge) thermistor temperature rise — the compressor is running far too hot.	Shortage of refrigerant / refrigerant leak, blockage in the refrigerant circuit, faulty discharge thermistor, failed outdoor fan, or a failing compressor.	Switch off & call
Outdoor LED 7 flashes (07)	Outdoor thermistor abnormality on any of the outdoor thermistors — detected as an open circuit, short circuit or a half-inserted connector.	Failed thermistor or a connector not fully seated. (Summit/Monozone models; on Multizone, thermistor faults are reported through the LD301/LD302 sub-codes instead.)	Book a service
Outdoor LED 8 flashes (08)	Acceleration defective — the compressor will not accelerate above its minimum speed.	Shortage of refrigerant charge or a mechanically failing compressor.	Switch off & call
Outdoor LED 9 flashes (09)	Communication error between the indoor and outdoor units.	On Summit/Monozone-era systems: the interface signal terminals C and D not connected, a faulty interconnecting cable, or PCB failure. Terminal designations vary by series.	Try this first Isolate the system at the breaker for 2 minutes and restore power. If the code returns, it is a wiring or board fault — book a technician.
Outdoor LED 10 flashes (10)	Abnormal power source — supply voltage outside the acceptable range.	Incorrect or unstable mains voltage, undersized/faulty supply wiring, or a faulty reactor in the outdoor unit.	Switch off & call
Outdoor LED 11 flashes (11)	Outdoor fan motor or fan drive circuit abnormality — the fan isn't running as commanded.	In Hitachi's own order: a defective fan motor or fan drive circuit, an obstruction around the outdoor fan, or a failed outdoor PCB.	Try this first Switch off at the isolator, check nothing is jamming the outdoor fan and clear debris around the unit, then restore power after 2 minutes. If it returns, book a technician.
Outdoor LED 12 flashes (12)	Outdoor fan motor fault — abnormal fan rotation.	Failed DC fan motor, seized bearing, blown fan fuse on the outdoor PCB, or PCB fan-drive failure.	Book a service
Outdoor LED 13 flashes (13)	Outdoor EEPROM / memory read error.	Corrupted or failed memory on the outdoor control board.	Book a service
Outdoor LED 14 flashes (14)	Active converter defective / over-voltage detected by the inverter power module.	Failed active converter circuit or power module (SPM) on the outdoor inverter board.	Switch off & call
Outdoor LED 15 flashes (15)	Outdoor PCB circuit abnormality — specifically the voltage-detection or current-detection circuit. The remedy is replacement of the outdoor unit controller.	Failed detection circuitry on the outdoor control PCB. Not implemented on every series.	Switch off & call

Multizone (multi-split) outdoor thermistor sub-codes — LD301 lit steady, count the LD302 blinks

Code	What it means	Likely cause	What to do
LD302 1 blink	Compressor overheat (OH) thermistor fault.	Failed or disconnected compressor thermistor.	Book a service
LD302 2 blinks	Defrost thermistor fault.	Failed or disconnected defrost thermistor on the outdoor coil.	Book a service
LD302 3 blinks	Outdoor ambient temperature thermistor fault.	Failed or disconnected outdoor air thermistor.	Book a service
LD302 4 blinks	Narrow (gas) pipe thermistor fault on indoor circuit 1.	Failed or disconnected branch-pipe thermistor at the outdoor unit.	Book a service
LD302 5 blinks	Wide (liquid) pipe thermistor fault on indoor circuit 1.	Failed or disconnected branch-pipe thermistor at the outdoor unit.	Book a service
LD302 6 blinks	Narrow (gas) pipe thermistor fault on indoor circuit 2.	Failed or disconnected branch-pipe thermistor at the outdoor unit.	Book a service
LD302 7 blinks	Wide (liquid) pipe thermistor fault on indoor circuit 2.	Failed or disconnected branch-pipe thermistor at the outdoor unit.	Book a service
LD302 8 blinks	Narrow (gas) pipe thermistor fault on indoor circuit 3.	Failed or disconnected branch-pipe thermistor at the outdoor unit.	Book a service
LD302 9 blinks	Wide (liquid) pipe thermistor fault on indoor circuit 3. On 5-port models, counts 4–7 can be ambiguous between circuits 1/4 and 2/5 — both branch thermistors need checking.	Failed or disconnected branch-pipe thermistor at the outdoor unit.	Book a service

Wired-controller H-LINK alarms — indoor unit, transmission and power supply (01–08) · ducted, cassette and light-commercial

Code	What it means	Likely cause	What to do
01	Indoor unit protection device activated — most commonly the condensate float switch detecting water backing up.	Blocked or kinked condensate drain, failed drain pump, or a faulty float switch.	Try this first Check the drain outlet outside for blockages or kinks. If water keeps backing up, book a service before it damages ceilings.
02	Outdoor unit protection device activated — high-pressure cut (PSH, 41.3 bar), a locked motor, or a power-supply phase abnormality.	Blocked outdoor coil or restricted airflow, refrigerant overcharge, a seized compressor, or supply phase problems.	Switch off & call
03	Transmission (communication) failure between the outdoor unit and the indoor unit(s).	Incorrect or damaged interconnecting control wiring, loose terminals, blown fuse, power off to one unit, DIP-switch/addressing error, or PCB failure.	Try this first Switch the whole system off at the isolator/breaker (both indoor and outdoor supplies if separate) for 2 minutes, then restore power and retry. If code 03 comes straight back, it is a wiring or board fault — book a technician.
04	Transmission failure between the outdoor main PCB and the inverter PCB.	Faulty cabling between the boards, no power reaching the inverter PCB, or PCB failure. (A trailing-dot variant, 04., indicates a different board-to-board link.)	Book a service
05	Abnormal power-source phase detected (three-phase light-commercial units).	Reversed phase connection, a missing phase, or a distorted supply waveform. Applies to 3N~400 V models — rare on single-phase residential equipment.	Switch off & call
06	Inverter supply voltage too low or too high.	Voltage drop or over-voltage at the outdoor unit, undersized or faulty supply cable, loose terminations, or failed inverter capacitors.	Switch off & call
07	Decrease in discharge gas superheat — liquid refrigerant is returning to the compressor.	Excessive refrigerant charge, faulty thermistor, incorrect piping/wiring, or an expansion valve locked open (often a disconnected EV connector).	Book a service
08	Excessively high discharge gas temperature at the top of the compressor.	Insufficient refrigerant charge or a refrigerant leak, restriction/blockage in the refrigerant circuit, or an expansion valve closed or clogged.	Switch off & call

Wired-controller H-LINK alarms — indoor sensors and fan (11–19) · ducted, cassette and light-commercial

Code	What it means	Likely cause	What to do
11	Indoor air inlet (return air) thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; or an indoor PCB sensor input fault.	Book a service
12	Indoor air outlet (discharge air) thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; or an indoor PCB sensor input fault.	Book a service
13	Indoor freeze-protection (liquid line) thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; or an indoor PCB sensor input fault.	Book a service
14	Indoor gas (suction) pipe thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; or an indoor PCB sensor input fault.	Book a service
19	Indoor fan motor protection device activated — the fan motor has overheated or stalled.	Blocked filters or return-air grille starving the fan, obstructed or seized fan, failed AC/DC fan motor, or over/under-current detected by the PCB.	Try this first Turn the system off, remove and wash the indoor filters (and, on ducted systems, check the return-air grille filter), let them dry fully, refit, then power cycle for 2 minutes. If code 19 returns the fan motor or board needs replacing.

Wired-controller H-LINK alarms — outdoor sensors (20–29) · ducted, cassette and light-commercial

Code	What it means	Likely cause	What to do
20	Compressor (top) thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; or outdoor PCB input fault.	Book a service
21	High-pressure sensor / discharge pressure transducer abnormality.	Transducer loose, disconnected, open or short circuited; or outdoor PCB input fault.	Book a service
22	Outdoor ambient air thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; or outdoor PCB input fault.	Book a service
23	Discharge gas thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; or outdoor PCB input fault.	Book a service
24	Outdoor evaporating temperature thermistor abnormality.	Sensor loose, disconnected, broken or short circuited; can also be logged when the outdoor fan motor locks during heating.	Book a service
29	Low-pressure sensor / suction pressure transducer abnormality.	Transducer loose, disconnected, open or short circuited; or outdoor PCB input fault.	Book a service

Wired-controller H-LINK alarms — system, capacity and addressing (31–38, b0, b1, b5) · ducted, cassette and light-commercial

Code	What it means	Likely cause	What to do
31	Incorrect capacity setting, or outdoor and indoor unit capacities do not match.	Wrong capacity code set on a board after a repair, or connected indoor capacity outside the allowed range (typically more than 130% or less than 50% of the outdoor unit).	Book a service
32	Fault or incorrect setting reported by another indoor unit on the same refrigerant circuit.	Another indoor unit on the same system has lost power, has a PCB failure, or has a wiring/addressing error — common on multi-splits and multi-head ducted systems.	Book a service
35	Incorrect indoor unit number setting — duplicated address on the same refrigerant system or H-LINK.	Two indoor units set to the same unit/refrigerant-cycle number, or more indoor units connected than the system allows.	Book a service
36	Indoor/outdoor unit combination is not compatible.	An indoor unit designed for a different refrigerant (R22/R407C) or a different product series has been connected to the outdoor unit.	Book a service
38	Abnormality in the protection-circuit pick-up (detection) circuit.	Incorrect connection to the outdoor or indoor PCB, or PCB failure — often seen after a board replacement or rewire.	Book a service
b0	Indoor unit model/capacity has not been set, or is set incorrectly.	Capacity DIP-switch or setting not configured after a PCB replacement.	Book a service
b1	Incorrect unit address or refrigerant cycle number setting.	Address set outside the valid range, or more than 64 indoor units addressed on the network.	Book a service
b5	Incorrect indoor unit number setting for the H-LINK type in use.	17 or more indoor units connected to a single H-LINK II system where fewer are permitted.	Book a service

Wired-controller H-LINK alarms — refrigerant pressure and protection devices (41–47) · ducted, cassette and light-commercial

Code	What it means	Likely cause	What to do
41	Cooling overload — the system is working near its high-pressure limit in cooling.	Outdoor pipe temperature above ~55 °C with compressor top temperature above ~95 °C: dirty or blocked outdoor coil, restricted airflow around the outdoor unit, or extreme ambient conditions.	Try this first Switch off, then clear vegetation, rubbish and stored items away from the outdoor unit so air can flow freely through and out of it, and hose loose dust off the coil fins from the outside (never with the power on, never with a pressure washer). Also wash the indoor filters. Restart after 2 minutes.
42	Heating overload — the system is working near its high-pressure limit in heating.	Indoor freeze-protection thermistor above ~55 °C with compressor top temperature above ~95 °C: blocked indoor filters, closed or blocked outlets, or restricted return air.	Try this first Wash the indoor/return-air filters, open any closed vents or zones, and clear furniture or curtains blocking the outlets. Power cycle for 2 minutes and restart. If it returns, book a technician.
43	Safety device activated due to a fall in compression ratio — discharge and suction pressures are too close together.	Compressor mechanical failure or inverter damage; can also be a failed pressure transducer or a badly incorrect charge.	Switch off & call
44	Safety device activated due to excessively high suction pressure.	Severe overload in cooling, high indoor temperature in heating, or an expansion valve locked open.	Book a service
45	Safety device activated due to excessively high discharge pressure.	Blocked outdoor heat exchanger or short-cycling airflow, excessive refrigerant charge, or air/inert gas in the refrigerant circuit.	Switch off & call
47	Safety device activated due to excessively low suction pressure (vacuum protection).	Refrigerant shortage or a leak, blocked pipework or filter drier, an expansion valve locked closed, or a locked fan motor.	Switch off & call

Wired-controller H-LINK alarms — inverter, compressor and electrical (48–EE) · ducted, cassette and light-commercial

Code	What it means	Likely cause	What to do
48	Over-current protection activated.	Overload or over-current at the compressor: failed inverter power module (DIP-IPM/IPM/PCB2), locked compressor, clogged heat exchanger or expansion valve failure.	Switch off & call
51	Inverter current sensor abnormality.	Current sensor mis-wired or failed, or failure of the control PCB / inverter power module.	Switch off & call
53	Inverter power module (IPM/DIP-IPM) protection — over-current, low voltage or overheating.	Inverter module or PCB2 failure, failing compressor, or a clogged outdoor heat exchanger causing the module to overheat.	Switch off & call
54	Inverter fin (heatsink) temperature abnormality — the inverter is running too hot.	Blocked or dirty outdoor heat exchanger, failed outdoor fan motor, or restricted airflow over the inverter heatsink.	Switch off & call
55	Inverter module abnormality on most current series. On some older Utopia/IVX/Set Free-derived series the same code instead means a remote-controller wiring short circuit.	Failure of the DIP-IPM/IPM or inverter PCB; or (older series) a short circuit on the wired-controller cable, a failed controller, or an indoor PCB fault. Confirm against the manual for your exact model.	Switch off & call
57	Outdoor fan motor abnormality — abnormal fan speed or fan controller protection.	Failed outdoor fan motor, wiring error between the main and fan PCBs, or fan controller over-current/over-temperature.	Book a service
EE	Compressor protection alarm — the system has locked itself out to protect the compressor. It cannot be reset from the remote controller.	Alarms 02, 07, 08, 45 or 47 have occurred three times within six hours. The underlying refrigerant, pressure or compressor fault must be found and fixed before the lockout is cleared.	Switch off & call

Wired controller — indoor unit, transmission and power supply alarms (01–08)

Code	What it means	Likely cause	What to do
1A	Abnormality of indoor fan controller fin temperature	Fin thermistor failure on the indoor fan controller, blocked airflow over the controller heatsink, or heat exchanger/filter clogging raising the controller temperature.	Book a service
1B	Activation of overcurrent protection on the indoor fan controller	Indoor fan motor drawing excessive current — locked rotor, bearing failure, winding short, or fan controller output stage failure.	Book a service
1C	Problem with the indoor fan controller current sensor	Current sensor failure or wiring fault on the indoor fan controller PCB.	Book a service
1D	Activation of indoor fan controller protection (driver IC error signal)	Driver IC error signal detected on the indoor fan controller — instantaneous overcurrent, earth fault on the fan motor, or fan controller PCB failure.	Book a service
1E	Abnormality of indoor fan controller voltage	Indoor supply voltage drop, undersized or loose supply wiring, poor terminal connections, or indoor power supply PCB failure.	Book a service
5A	Abnormal fin temperature on the outdoor fan controller	Outdoor fan motor failure, fin thermistor failure, or a clogged/dirty outdoor heat exchanger preventing heat rejection from the fan controller heatsink.	Book a service
5B	Activation of overcurrent protection on the outdoor fan controller	Outdoor DC fan motor drawing excessive current — seized bearings, obstructed fan, winding short, or fan controller output failure.	Book a service
5C	Outdoor fan controller sensor abnormality / fan controller protection	Current sensor failure, low supply voltage, overcurrent, earth fault on the fan motor, controller temperature rise, or outdoor fan motor abnormality.	Book a service
09	Activation of protection device for the outdoor fan motor	Outdoor fan motor overheat or motor lock-up — seized bearings, debris/leaves jamming the fan, fan motor winding failure, or outdoor fan driver circuit failure. Often accompanies high-pressure trips because head pressure cannot be rejected.	Book a service
17	Abnormality of the thermistor built into the wired remote controller	Failed sensor inside the wall controller, or a damaged/short-circuited controller cable. Unit typically falls back to the return-air sensor and controls poorly.	Book a service
18	Abnormality of the indoor fan system — DC fan motor step-out / speed feedback fault	Indoor DC fan motor stalled or stepped out of sync, blocked filter or coil creating excessive static pressure, obstructed blower wheel, failed fan motor Hall sensor, or indoor fan controller failure. Distinct from code 19, which is the fan thermal protection device.	Book a service

Wired controller — outdoor sensor alarms (20–29)

Code	What it means	Likely cause	What to do
25	Abnormality of the outdoor heat exchanger gas pipe thermistor	Thermistor failure, short circuit, or incorrect/broken/disconnected sensor wiring at the outdoor coil gas line. Causes poor defrost and capacity control.	Book a service

Wired controller — system, capacity and addressing alarms (31–38, b0, b1, b5)

Code	What it means	Likely cause	What to do
39	Abnormal running current at the constant-speed compressor	Current sensor failure, momentary power failure, blown fuse, supply voltage drop, genuine compressor overcurrent, or abnormal power supply. On residential twin/constant-speed outdoor units this commonly precedes compressor failure.	Switch off & call

Reference compiled from Hitachi service and operation documentation. Codes and meanings are provided as general guidance for the Australian residential range and can differ between model series; no affiliation with Hitachi is implied.

Found your code?

Tell us the code when you book — diagnosis starts before we arrive

Fault finding across Perth from $165 inc GST — all brands, splits and ducted. Quoting the fault code gives us a head start on where to look; we then test and confirm the actual fault on site before any part is ordered, so you shouldn't end up paying for a part you didn't need.

Book a repair Call 0434 951 341

The honest next question

Repair or replace your Hitachi?

A fault code tells you something's wrong — it doesn't tell you whether the unit is worth fixing. The age of the system is the honest starting point:

Under ~8 years

Repair usually wins

Most fault codes on a young unit trace to something sensible — a sensor, a board, a blocked drain — and a proper diagnosis first means you pay for the diagnosed fault, not guesswork. A Hitachi under eight years old is normally worth fixing.

8–15 years

Get both numbers

This is judgement-call territory. A cheap fix on a working system is still good money — but if the fault is compressor- or inverter-side, the repair can be a third of a new unit's installed price. Ask for the repair quote and the replacement quote together and decide once, with real numbers.

15+ years

Replacement is usually better money

Efficiency has moved a long way in a decade — a modern unit cools the same room for a fraction of the running cost — and parts supply for older series thins out with age. At this age, money spent on another repair is usually money towards a unit that's near the end either way.

What replacement actually costs: a like-for-like split swap in Perth typically runs $1,700–$3,800 supply and installed — about the same as a first-time install, because decommissioning the old unit (legal refrigerant reclaim, removal, disposal) offsets the saving from reusing the circuit. The existing circuit can usually be reused if it's compliant; pipework is replaced in almost every case, or properly flushed where new runs aren't practical. Full numbers by size are in our Perth cost guide and the installed price directory.

Get a replacement quote Call 0434 951 341

Frequently Asked Questions

How do I read the TIMER lamp on my Hitachi wall split?

Count the flashes between the pauses. Two flashes isn't a fault — it means the outdoor unit is in forced or test operation. Four flashes means the fault sits in the outdoor unit, and the detail is on the outdoor board's LED behind the service cover, which is a technician's job to read.

What are the LD301 and LD302 lights?

They're diagnostic LEDs on Multizone (multi-split) outdoor units. When LD301 is lit steadily and LD302 blinks, the blink count identifies which thermistor has failed (1 to 9). If LD301 and LD302 are lit together with LD303, that's an overload condition rather than an alarm.

My ducted Hitachi shows a two-digit alarm — is that the same as the lamp codes?

No, and this catches people out. Wired-controller systems use Hitachi's H-LINK alarm numbering, which is unrelated to the wall-split lamp counts. Alarm 02 on a wired controller is not the same fault as two TIMER flashes on a wall split. Use the section that matches your equipment.

Can I reset a Hitachi alarm?

Power off at the isolator for two minutes and restart. Genuine faults come straight back — and Hitachi's protection alarms (high pressure, overload) usually mean something physical needs fixing, like a blocked coil or restricted airflow, before the system will hold.

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