High
F9 or L9 or F8 or L8 on Ideal Logic Combi C24 C30 C35

Your boiler's main internal computer is failing to communicate correctly with its internal control systems, preventing it from safely starting up.

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

PCB UNCONFIGURED/FAULTY OR GAS VALVE SHORT CIRCUIT

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

F9View →L9View →F8View →L8View →

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