High
ON OFF FLASH on Baxi Suprima 70

Your boiler has detected an issue with the electrical power connection, meaning the wiring likely doesn't match the safety standards required to operate.

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

Live and neutral reversed error

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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