Emergency
ON OFF FLASH on Baxi Suprima 50

Your boiler has detected an electrical wiring issue, meaning the power supply polarities are the wrong way around and need correcting for safety.

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

Live and neutral reversed error

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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