Medium
FD 231 on Worcester Bosch Greenstar 12i System

Your boiler has detected that the electricity supply to it was recently 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

Mains power error - Electrical power interruption.

From this model's manual
Verified against the Worcester Bosch Greenstar 12i System installation & service manual.
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

Locate the fused spur or plug socket supplying power to the boiler.Switch the power off for 60 seconds, then switch it back on to reset the system.Check that your home's consumer unit has not tripped a circuit breaker.

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