High
A09 on Ferroli iBoiler 28

Your boiler has detected a problem with how it controls the gas flow, meaning it cannot light safely and has shut down to protect your home.

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

Gas valve error – wiring could be disconnected or error with gas valve

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 →A06View →F43View →

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