High Lockout
12-69 on Daikin D2CND

Your boiler is struggling to automatically adjust its internal settings to ensure the gas burns efficiently, which may lead to it shutting down for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Offset adaptation at limit

What causes this fault?

This fault occurs when the boiler's control system can no longer fine-tune the gas and air mixture to maintain a safe and efficient flame. It is usually caused by a worn-out sensing electrode failing to detect the flame correctly or a gas valve that is drifting out of its required operating range.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

12-68View →12-67View →12-65View →

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