High
5 P3 on Ariston Clas Net One

Your boiler has detected that the flame has gone out unexpectedly while it was running, which has caused it to stop heating to ensure your safety.

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

Flame cut-off

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

5P1View →5P2View →501View →

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