The flue temperature has met / surpassed the maximum limit.
- Is the tank full of water? This error code will appear if the tank is dry-fired. - Measure actual Flue temperature.
- Use an ohmmeter to check resistance on flue temperature sensor.
- Replace sensor if it does not pass the resistance test.
- If Flue temperature does not return to normal within 15 minutes, this error shall become an F07 fault code.
- Error will clear automatically if Flue temperature returns to normal within 15 minutes.