Emergency
E03 on Ariston Genus 24 MFFI

Your boiler has detected an abnormally high temperature inside the system even though it isn't currently trying to heat your home.

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

Flow temperature over 100°C while boiler is not in operation (stand-by)

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

E04View →

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