Medium
231 on Worcester Bosch Greenstar 28CDi

Your boiler has detected that the electrical power supply to it has been interrupted or is unstable.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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 28cdi Compact installation & service manual, page 65.
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 appliances in your home are working to confirm your main power supply is stable.Locate the fused spur switch for your boiler and ensure it is firmly in the 'on' position.Switch the boiler off at the fused spur for 30 seconds, then switch it back on to reset the system.

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