High Lockout
C2 on Ideal Logic Combi C24 C30 C35

Your boiler has lost communication with its internal computer chip, meaning the main control board no longer recognizes the specific model it is supposed to be operating.

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

BCC Fault

What causes this fault?

This fault occurs when the boiler's main control board loses the vital data connection to its identity chip, effectively 'forgetting' which model it is. The most common reason is a loose or failing Boiler Chip Card (BCC) that has vibrated out of place or suffered a small electrical surge that corrupted its memory.

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

L2View →F2View →

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