Medium
231 on Worcester Bosch Greenstar 12i System

Your boiler has detected that the electricity supply to it has been interrupted or is currently unstable.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

FD Mains power error - electrical power interruption

From this model's manual
Verified against the Worcester Bosch Greenstar 12i System installation & service manual, page 63.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if other electrical appliances in your home are working to rule out a general power cutLocate the boiler's fused spur switch and ensure it is firmly in the 'on' positionCheck your consumer unit (fuse box) to see if the circuit breaker for the heating system has tripped and reset it if necessary

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