High
flame failure on Ariston Clas One

Your boiler is trying to start but cannot detect a flame, meaning it is currently unable to provide heating 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

NB.: It may be necessary to reset the flame failure reset a number of times during this operation

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 →5P3View →

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