BoilerFaultCodesDaikin 12-67 Fault Code
Also written as 1267 — same fault.
The Daikin 12-67 fault code means: your boiler's flame sensor is detecting an unusual reading that is outside of its normal operating range, which has caused the system to stop as a safety precaution.. It appears on 1 Daikin model in our database.
Technical description: Ion base value exceeds the upper factory limit – try resetting the boiler
What causes the Daikin 12-67 fault?
This fault occurs when the boiler's internal sensors detect an electrical current that is too high or unstable during the combustion process. It is often caused by a buildup of carbon on the flame-sensing probe or a fault in the wiring that prevents the control board from accurately monitoring the burner. As a safety measure, the boiler shuts down because it cannot be certain that the flame is burning correctly or safely.
DIY fix possible
Locate the reset button on the boiler control panelPress and hold the reset button for 2-3 secondsWait for the boiler to complete its restart sequence and check if the code clears
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Gas Safe Register →Daikin models that show the 12-67 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Daikin 12-67 fault code information on this page is sourced and cross-checked against the official Daikin service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026