Medium
231 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected a brief loss of electricity or a dip in power, causing it to shut down temporarily.

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 Cdi 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 that your boiler's power supply switch is turned onCheck your home's fuse box to ensure the boiler's circuit breaker has not trippedPress the reset button on the boiler's front panel to see if it restarts

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