Daikin Aircon UF Error Code
Use this Daikin UF error code guide to confirm the source table meaning, capture the reporting equipment and model, and match the service manual before diagnosis. Match the model first; same-looking codes can point to different rows.
What does Daikin UF mean?
Daikin UF is listed as system is not set yet, system not set yet, and auto-address malfunction or addressing inconsistency in mixed model-family source rows, including VRV X RXQ-A(N)R cooling only, VRV IV+ REYQ / REMQ heat recovery, VRV 5-S RXYSA R32, VRV 5 Heat Recovery REMA / REYA R32, VRV 5 Heat Pump RYMA / RXYA R32, and Sky Air FNA R32 - test-run diagnostic. The loaded row is source-backed by official diagnostic material. Do not collapse this code across model families; use the model, series, or system type to choose the right row. Confirm the exact model, series, or signal row before accepting a parts quote.
Choose the matching source row
The same visible code has more than one source-backed meaning. Match the model family, system type, or reporting unit before approving parts.
| Code | What it means | What to check first |
|---|---|---|
| SkyAir | System is not set yet | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
| VRV X RXQ-A(N)R cooling only | System not set yet | Match this row to the installed model or reporting unit, then use the source-specific checks below. |
| UF-01 - system | Auto-address malfunction or addressing inconsistency | Check whether the transmission-wired unit count matches the powered unit count, or wait for initialisation to finish. Match the alternating UF-01 display to the system source row. |
| UF-05 - system | Stop valve closed or incorrect during the system test run | Open the stop valves. Match the alternating UF-05 display to the system source row. |
| VRV 5-S R32 - UF | Auto-address inconsistency | Check stop valves and confirm that the selected indoor unit's piping and wiring reach the correct outdoor unit. |
| VRV 5 Heat Recovery R32 - UF | Indoor-to-BS-unit wiring or piping mismatch | Confirm wiring and piping between each indoor and BS unit against the connection check. |
| VRV 5 Heat Pump R32 - UF | Indoor-to-SV-unit wiring or piping mismatch | Confirm wiring and piping between each indoor and SV unit against the connection check. |
| Sky Air FNA R32 - UF (test-run diagnostic) | Inter-unit or branch wiring is incorrect | Confirm the indoor model is FNA25~60A2VEB(9), record the reporting controller, and follow the matching Daikin service procedure. |
- Code
- SkyAir
- What it means
- System is not set yet
- What to check first
- Match this row to the installed model or reporting unit, then use the source-specific checks below.
- Code
- VRV X RXQ-A(N)R cooling only
- What it means
- System not set yet
- What to check first
- Match this row to the installed model or reporting unit, then use the source-specific checks below.
- Code
- UF-01 - system
- What it means
- Auto-address malfunction or addressing inconsistency
- What to check first
- Check whether the transmission-wired unit count matches the powered unit count, or wait for initialisation to finish. Match the alternating UF-01 display to the system source row.
- Code
- UF-05 - system
- What it means
- Stop valve closed or incorrect during the system test run
- What to check first
- Open the stop valves. Match the alternating UF-05 display to the system source row.
- Code
- VRV 5-S R32 - UF
- What it means
- Auto-address inconsistency
- What to check first
- Check stop valves and confirm that the selected indoor unit's piping and wiring reach the correct outdoor unit.
- Code
- VRV 5 Heat Recovery R32 - UF
- What it means
- Indoor-to-BS-unit wiring or piping mismatch
- What to check first
- Confirm wiring and piping between each indoor and BS unit against the connection check.
- Code
- VRV 5 Heat Pump R32 - UF
- What it means
- Indoor-to-SV-unit wiring or piping mismatch
- What to check first
- Confirm wiring and piping between each indoor and SV unit against the connection check.
- Code
- Sky Air FNA R32 - UF (test-run diagnostic)
- What it means
- Inter-unit or branch wiring is incorrect
- What to check first
- Confirm the indoor model is FNA25~60A2VEB(9), record the reporting controller, and follow the matching Daikin service procedure.
What to do now
Use these steps to record evidence and match the installed model to its service manual before diagnosis or a repair quote.
Record UF and match the service manual
Record UF and stop there; the source table gives no customer reset procedure. Arrange diagnosis with the matching service manual.
No manufacturer reset steps listed for UF
Capture the complete UF error code and model stickers first. The source table lists the meaning but no customer reset procedure; do not treat a generic power-cycle as manufacturer guidance.
Send these to us
UF error code, a clear display photo, Daikin indoor and outdoor model stickers, the controller, gateway, or unit that reported the code, operating mode and affected area, and any power or setting changes made after the code appeared
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 |
|---|---|
| Singapore / model note | Official Daikin SM-TS3 self-diagnosis row. Manual causes: Improper indoor-outdoor or outdoor-outdoor transmission wiring; Check operation not executed; Stop valve is not opened. |
| Singapore / model note | Official Daikin RXQ6-48A(N)R cooling-only service-manual row. Confirm the installed model and matching regional manual before diagnosis; this source is not claimed as universal across every Daikin VRV generation. |
| Singapore / model note | Official Daikin 4PEN561154-1C overview row for REYQ8~20 and REMQ5U7Y1B VRV IV+ heat-recovery systems. The guide refers technicians to the service manual for the complete code list and detailed troubleshooting. |
- Source detail
- Singapore / model note
- What it says
- Official Daikin SM-TS3 self-diagnosis row. Manual causes: Improper indoor-outdoor or outdoor-outdoor transmission wiring; Check operation not executed; Stop valve is not opened.
- Source detail
- Singapore / model note
- What it says
- Official Daikin RXQ6-48A(N)R cooling-only service-manual row. Confirm the installed model and matching regional manual before diagnosis; this source is not claimed as universal across every Daikin VRV generation.
- Source detail
- Singapore / model note
- What it says
- Official Daikin 4PEN561154-1C overview row for REYQ8~20 and REMQ5U7Y1B VRV IV+ heat-recovery systems. The guide refers technicians to the service manual for the complete code list and detailed troubleshooting.
What to check before repair
The source table establishes the code meaning, not a repair procedure. Capture evidence first; model-specific tests belong to the matching service manual.
| You can check | Technician should confirm |
|---|---|
| Photograph the complete UF error code before taking any action. | Confirm UF exactly and record which controller, gateway, or unit reported it. |
| Capture the Daikin indoor and outdoor model stickers and identify which controller or unit reported it. | Match the indoor and outdoor model stickers, installed family, and reporting equipment to the source scope. |
| The source table provides no customer reset procedure. Preserve the evidence and use the matching service manual for any system action. | Follow the matching service-manual procedure and keep measured test evidence before naming a failed part. |
- You can check
- Photograph the complete UF error code before taking any action.
- Technician should confirm
- Confirm UF exactly and record which controller, gateway, or unit reported it.
- You can check
- Capture the Daikin indoor and outdoor model stickers and identify which controller or unit reported it.
- Technician should confirm
- Match the indoor and outdoor model stickers, installed family, and reporting equipment to the source scope.
- You can check
- The source table provides no customer reset procedure. Preserve the evidence and use the matching service manual for any system action.
- Technician should confirm
- Follow the matching service-manual procedure and keep measured test evidence before naming a failed part.
Source-bounded repair decision
Daikin UF confirms the source-table fault label, not a failed part or repair procedure. Match the installed model to its service manual and require measured diagnostic evidence before approving parts, settings, or refrigerant work.
Whether the reporting controller or unit and exact installed model are confirmed.
What the matching service-manual procedure and measured tests show.
Whether the proposed repair names the evidence for the failed part or condition.
Daikin UF questions
What does the Daikin UF error mean?
Can I fix a Daikin UF error myself?
Is it safe to keep running the aircon with a UF error?
What causes a Daikin UF error?
Will a Daikin UF error need a repair or a full replacement?
What should I send a technician about a Daikin UF error?
Confirm the fault
Share the error code, model number and symptoms so we can assess the likely cause.
Not the right code?
Browse the full Daikin list or check a few codes in the same fault category.
Ready to get started?
Tell us what’s going on. Symptoms, setup, photos, anything we should know. We’ll assess and come back with the right next step.
Read next
Use this quote-check guide only after the matching service manual identifies the diagnostic path.