High Lockout
10-65 on Daikin D2CND

Your boiler has detected an electrical issue with the gas control system and has shut down as a safety precaution.

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

Gas valve current fault, try resetting the boiler

What causes this fault?

This fault occurs when the boiler's main computer loses the ability to correctly control the electrical signal sent to the gas valve. The most common reason is a physical failure of the internal solenoids within the gas valve or a communication break in the wiring connecting it to the control board. For safety reasons, the boiler immediately stops ignition because it can no longer guarantee the precise regulation of gas flow.

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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