High Lockout
C0 on Ideal Logic Combi C24 C30 C35

Your boiler's main control chip has lost communication with the circuit board, essentially meaning the brain and body are no longer speaking to each other.

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 Activation Fault

What causes this fault?

This fault occurs when the small memory chip that stores the boiler's identity fails to communicate with the main control board. The most common reason is a physical connection failure or a software glitch that causes the boiler to lose its configuration settings, rendering it unable to operate safely.

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 →L2View →F2View →

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