High Lockout
C0 on Ideal Logic+

Your boiler's internal computer chip has lost connection or failed to communicate with the main control board, preventing the system from starting.

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

Boiler chip card (BCC) activation fault

What causes this fault?

This fault occurs when the main control board can no longer read the data from the small plug-in chip that tells the boiler exactly how to operate. The most common reason is that the chip has vibrated loose, or the electronic connection between the chip and the board has failed due to age or a power surge.

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

C2View →F2View →

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