Emergency
5 02 on Ariston Clas Net One

Your boiler has detected a flame inside when it should be turned off, which is a significant safety concern that requires immediate professional attention.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Flame detected with gas valve closed

Engineer required

This is a emergency 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

5 01View →5 04View →

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