ErrorCodeDoctor
Daikin Air Conditioner J9 error code
The J9 error means your Daikin air conditioner detected a fault with a gas pipe thermistor in the refrigerant circuit. Contact a qualified technician to inspect and replace the thermistor.
Common causes
- Defective connection of thermistor
- Defective gas pipe thermistor
- Defective outdoor unit PCB
How to fix it
-
1
Contact a qualified technician to inspect and replace the gas pipe thermistor
Related Daikin Air Conditioner error codes
A0
An external protection device connected to the indoor unit has been activated
A1
A fault was detected in the indoor unit PCB (control board)
A3
The drain level control system has detected an abnormality — drain may be clogged
A5
Freeze-up protection (cooling) or high pressure control (heating) has activated — check the air filter
J9 error — frequently asked questions
What does the J9 error mean on a Daikin air conditioner?
A refrigerant circuit gas pipe thermistor has a fault
What causes the J9 error?
The J9 error is usually caused by: Defective connection of thermistor; Defective gas pipe thermistor; Defective outdoor unit PCB.
Can I fix the J9 error myself?
This is rated a hard fix — it often requires tools, parts, or experience, and may be safer left to a professional technician.
How much does it cost to fix the J9 error?
Fixing the J9 error on a Daikin air conditioner typically costs $80–$250, depending on parts and whether you do it yourself or hire a technician.
Is it safe to keep using my air conditioner with the J9 error?
We'd recommend addressing the J9 error before continuing to use the air conditioner, since hard-rated issues often involve a real fault rather than a minor glitch.