High
F8 on Ferroli Optimax

Your boiler is failing to stay alight after it tries to start up, meaning it cannot provide heat or hot water.

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

No flame after the ignition phase. Possible causes: PCB trouble; Mains interference.

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

A01View →F01View →

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