Low
305 on Worcester Bosch Greenstar 12i System

Your boiler is currently waiting for a timed delay to finish before it starts heating your water again, which is a normal protective feature.

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

Anti fast cycle mode (Domestic Hot Water keep warm function. Diverter valve is held in hot water position for a period of time (determined by the software) after hot water demand (only available when using the optional integral diverter valve kit).

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.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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