High
ON OFF FLASH on Baxi Solo

Your boiler has detected that the electrical wiring coming into the unit is connected the wrong way around, causing it to shut down for safety.

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.

What the manual says

Manufacturer manual

Live and neutral reversed error

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the electrical supply to the boiler has been wired incorrectly, meaning the electricity is flowing in the opposite direction than intended. It most commonly happens after recent electrical work in the home or if a new plug socket has been installed incorrectly near the heating system.

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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