Daikin aircon HJ error code
Use this Daikin HJ error code guide to decide whether the display is only a status row, what to capture, and when a real fault still needs diagnosis.
What does Daikin HJ mean?
Daikin HJ is listed as malfunction of thermal storage tank water level in Ceiling Cassette, Ceiling Suspended, Inverter Split rows such as General RA self-diagnosis guide, SkyAir. The loaded row is source-backed by official diagnostic material. Confirm the exact model, series, or signal row before accepting a parts quote.
A status or reminder row is being shown rather than a confirmed breakdown.
The display may need clearing or monitoring, depending on the model manual.
A separate fault should be checked if cooling is still abnormal.
What to do now
Use these steps before another reset or parts quote.
Treat it as a fault signal
If HJ is only a status row, monitor it; if cooling is still abnormal, treat that symptom as the fault.
Reset HJ once
Capture the HJ display and check whether cooling is actually abnormal before resetting or booking a repair.
Send these to us
HJ error code, a clear display photo, Daikin model stickers, affected rooms, reset result, and whether cooling is actually abnormal
Source-specific guidance
These diagnostic-reference notes help match the code to the exact model. Electrical, refrigerant, wiring, resistance, and component checks are technician work, not DIY steps.
| Source detail | What it says |
|---|---|
| Source repair action | Stop the system if it smells burnt, leaks, or trips power; note the exact model and code before booking diagnosis. |
| Singapore / model note | Official Daikin SM-TS3 row; use only where the system has thermal-storage tank or matching water-level hardware. |
What to check before repair
Use this split to separate safe evidence capture from the tests a technician should prove before quoting parts.
| You can check | Technician should confirm |
|---|---|
| Before resetting HJ, take a clear display photo. | Confirm whether HJ is a status row or an active fault on that model. |
| Capture the Daikin indoor and outdoor model stickers so the correct family row is used. | Check if cooling, fan, or drainage performance is actually abnormal. |
| Note whether one room, several rooms, or the whole system is affected, plus whether it returns after one reset. | Clear the reminder or status only when the manual confirms it is not a fault. |
What changes the next step
These clues decide whether the first check is room-side, shared outdoor-side, refrigerant-side, source-table, or model-family confirmation.
| What you see | What it points to |
|---|---|
| Only one indoor unit shows HJ. | The affected room, indoor board path, wiring route, or local component should be checked first. |
| Several rooms or the outdoor unit show the same HJ fault. | The shared outdoor side, power path, communication trunk, or refrigerant circuit needs priority checking. |
| The fault returns immediately after one reset. | Start with the source-row diagnostic branch before approving parts. |
| The model family is different from the row you found online. | Use the model or series filter first; same-looking codes can still belong to different diagnostic tables. |
| The model belongs to Ceiling Cassette, Ceiling Suspended, Inverter Split rows such as General RA self-diagnosis guide, SkyAir. | The loaded row is source-backed by official diagnostic material. Use the matching source row before quoting parts. |
Monitor or diagnose decision
Daikin HJ may not need repair if the manual treats it as a status row. If cooling is still abnormal, treat it as a separate diagnostic issue.
Status rows should not trigger parts replacement by themselves.
Cooling symptoms matter more than the display if the manual says no active fault is present.
A separate active fault should be diagnosed if performance remains abnormal.
Daikin HJ questions
What does the Daikin HJ error mean?
Can I fix a Daikin HJ error myself?
Is it safe to keep running the aircon with a HJ error?
What causes a Daikin HJ error?
Will a Daikin HJ error need a repair or a full replacement?
What should I send a technician about a Daikin HJ error?
Confirm the fault
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Read next
Use these if the quote mentions the parts, checks, or repair path this code points to.