Emergency
E21 on Ariston Genus Premium

Your boiler has detected that the electrical wiring coming into the unit is connected incorrectly, which is a safety conflict between the live and neutral wires.

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

Error in the electrical connection (live and neutral crossed)

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

E20View →

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