High
ignition failure on Ariston Clas One

Your boiler has failed to start because it cannot detect a flame, likely due to a gas supply issue or an internal ignition problem.

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

The boiler will signal a shutdown due to ignition failure after 7 seconds if the gas cock is closed

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

501View →504View →

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