Daikin Air Conditioner Error Codes & Flashing Green Light
Is your Daikin air conditioner flashing a green light, displaying an error code or not working correctly? This guide to Daikin air conditioner error codes explains how to check fault codes, what common warning signs may mean, and when professional air conditioning repair may be required.
Why Is the Green Light Flashing on My Daikin Air Conditioner?
A flashing green operation light on a Daikin air conditioner usually means the system has detected a fault or abnormal operating condition. The exact cause can vary depending on the Daikin model and system type.
Before arranging a repair, you can check whether the system has stored an error code. The error code can help identify which part of the air conditioner requires attention.
If the unit has stopped cooling or heating, repeatedly shuts down, or the green light continues flashing after restarting the system, professional diagnosis may be required.
How to Check a Daikin Air Conditioner Error Code
If your Daikin split system is flashing a green light or has stopped operating, you may be able to retrieve the fault code using the wireless remote controller.
For many Daikin split-system wireless remotes:
- Point the remote controller towards the indoor unit.
- Press and hold the CANCEL / TIMER CANCEL button for about 5 seconds, until the code indication starts flashing on the remote display.
- Press the CANCEL / TIMER CANCEL button repeatedly. The remote will cycle through the available fault codes.
- Listen for a long continuous beep from the indoor unit. The code showing on the remote when you hear the long beep is the detected fault code.
- Write the code down — for example U4, A5 or L5 — along with the model number of your air conditioner. This information can help the technician diagnose the problem.
To exit the fault-code display, hold the CANCEL / TIMER CANCEL button for approximately 5 seconds. On compatible models, the display will also return to normal automatically if no button is pressed for about one minute.
Important: Daikin uses different remote and wired controllers across its air conditioning range, so this procedure does not apply to every model. If your controller does not have a CANCEL / TIMER CANCEL button, refer to the operation manual for your specific model.
Common Daikin Air Conditioner Error Codes
Daikin air conditioner error codes can help identify faults detected by the system. The exact meaning of a code can vary depending on the model and type of air conditioner, so the information below should be used as a general guide. Always check the documentation for your specific Daikin model or have the fault diagnosed by a qualified technician.
| Code | Daikin Fault / Possible Meaning |
|---|---|
| 00 | Normal – no fault detected |
| UA | Indoor/outdoor unit combination fault |
| U0 | Refrigerant shortage |
| U2 | Voltage or main circuit abnormality |
| U4 | Communication fault between indoor and outdoor units |
| A1 | Indoor unit PCB fault |
| A5 | High-pressure control or freeze-up protection |
| A6 | Indoor fan motor fault |
| C4 | Indoor heat exchanger temperature sensor fault |
| C9 | Indoor air temperature sensor fault |
| EA | Cooling/heating changeover fault |
| E1 | Outdoor unit circuit board fault |
| E5 | Compressor overload protection activated |
| E6 | Compressor start-up/lock fault |
| E7 | Outdoor DC fan motor fault |
| E8 | Input overcurrent |
| F3 | High discharge-pipe temperature control |
| F6 | High-pressure control during cooling |
| H6 | Compressor position detection fault |
| H9 | Outdoor temperature sensor fault |
| J3 | Discharge-pipe temperature sensor fault |
| J6 | Outdoor heat exchanger temperature sensor fault |
| L4 | Inverter heatsink temperature too high |
| L5 | Output overcurrent detected |
| P4 | Inverter heatsink temperature sensor fault |
Important: An error code helps identify the area of the air conditioner where a fault has been detected, but it does not necessarily identify the exact component that needs replacing. If the fault returns, the system will not operate, or you are unsure of the cause, arrange for the system to be diagnosed by a qualified air conditioning technician.
Daikin Error Code U4 – What Does It Mean?
Daikin error code U4 indicates a communication problem between the indoor and outdoor units.
This means the air conditioner has detected that the indoor and outdoor units are not communicating correctly. The system may stop operating and the green operation light may flash.
If U4 appears on your Daikin air conditioner, write down the error code and the model number of the system. If the fault continues or returns after restarting the system, the air conditioner should be checked by a qualified technician.
Daikin Error Code F3 – What Does It Mean?
Daikin error code F3 relates to discharge pipe temperature control.
The fault indicates that the air conditioner has detected an abnormal condition relating to the discharge pipe temperature. The system may stop operating to protect the equipment.
An F3 fault requires proper diagnosis to determine what is causing the abnormal temperature condition. If F3 appears on your Daikin air conditioner, record the fault code and model number and arrange for the system to be inspected by a qualified air conditioning technician.
Daikin Green Light Blinking and Air Conditioner Not Working
If your Daikin air conditioner has stopped working and the green operation light is blinking, the system may have detected a fault.
Use the fault-code checking procedure above to retrieve the stored error code from the Daikin remote controller. When cycling through the codes, listen for the long beep from the indoor unit. The code displayed when the long beep sounds is the current fault code.
Write down the fault code and the model number of your Daikin air conditioner. This information can help the technician identify the problem when arranging a repair.
If the system cannot be reset or continues to display a fault, contact HeatNCool Tech on 03 8288 1784 to arrange for a technician to inspect and repair the system.
Need Help With a Daikin Air Conditioner Fault?
If your Daikin air conditioner is displaying an error code, flashing a green light or has stopped cooling or heating, HeatNCool Tech can help.
Our technicians provide professional air conditioning fault diagnosis and repairs across Melbourne. If possible, have your Daikin model number and error code available when booking, as this can help us prepare for the service call.
Daikin Air Conditioner Error Code FAQs
1. Why is the green light flashing on my Daikin air conditioner?
A flashing green operation light can indicate that the Daikin air conditioner has detected a fault. You can use the remote controller to check whether the system has stored an error code. If the system has stopped operating or the light continues flashing, professional diagnosis may be required.
2. How do I check the error code on my Daikin air conditioner?
On compatible Daikin wireless remotes, point the remote towards the indoor unit and press and hold the CANCEL button for approximately 5–6 seconds until 00 appears on the display. Press CANCEL repeatedly to cycle through the fault codes. A short beep indicates the displayed code is not the current fault, while a long beep indicates the current error code.
3. What does Daikin error code U4 mean?
Daikin error code U4 indicates a signal transmission or communication error between the indoor and outdoor units. If the U4 fault continues or returns after the system is restarted, arrange for the air conditioner to be professionally diagnosed.
4. What does Daikin error code F3 mean?
Daikin error code F3 relates to discharge pipe temperature control. If F3 is displayed, record the code and the air conditioner’s model number and arrange for a qualified technician to diagnose the cause.
5. What does 00 mean on a Daikin air conditioner remote?
When entering the fault-code checking mode on compatible Daikin remotes, 00 will flash on the remote display. You then press the CANCEL button repeatedly to cycle through the available fault codes and listen for the long beep that identifies the current fault.