Daikin Error Code C9: Suction Air Thermistor Fault
Warning: Your Daikin HVAC system has detected a fault with the suction air thermistor. It's safe to operate, but you should schedule a professional repair soon.
How to Fix Daikin Code C9
- Turn off your HVAC system at the thermostat to prevent further wear.
- Contact a Daikin professional for repair. They have the tools and expertise to diagnose and fix the issue safely.
How to Reset Daikin Code C9
- Turn off the unit using the remote control or wall controller.
- Turn off the circuit breaker for the outdoor and indoor units. Wait 60 seconds.
- Restore power at the breaker.
- Turn the unit on with the remote control. If the error returns, the fault needs professional diagnosis.
What does C9 mean?
The Daikin C9 error indicates a problem with the suction air thermistor, a temperature sensor that helps regulate your HVAC system's performance. This issue doesn't pose an immediate safety risk, but it can lead to reduced comfort and system efficiency if left unaddressed. The thermistor might be faulty or the wiring could be damaged.
Affected Models
Replacement Parts
| Part | OEM Number | Est. Cost |
|---|---|---|
| Suction Air Thermistor | 42576C0002 | — |
Related Codes on Same Models
| Code | Description | Severity |
|---|---|---|
| A1 | Indoor PCB Defective | Warning |
| A3 | Drain Level System Fault | Warning |
| A5 | Freeze-Up/Overheat Protection | Warning |
| A6 | Fan Motor Lock/Overcurrent | Warning |
| C4 | Heat Exchanger Thermistor Fault | Warning |
| E1 | Outdoor PCB Defective | Warning |
| E3 | High Pressure Switch Activated | Warning |
| E4 | Low Pressure Switch Activated | Warning |
| E5 | Compressor Motor Lock | Warning |
| E6 | Standard Compressor Motor | Warning |