Low
328 on Worcester Bosch Greenstar 27CDi

Your boiler has briefly lost power, likely due to a minor power cut or a loose plug connection.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Brief mains voltage failure

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual, page 82.
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 switch is firmly in the 'on' position.Check your household consumer unit to ensure the circuit breaker for the heating system hasn't tripped.Ensure the plug socket supplying the boiler is fully pushed in if it is not hard-wired.

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