Low
305 on Worcester Bosch Greenstar 4000

Your boiler is perfectly fine and is simply taking a short, programmed break to prevent excessive wear on its parts.

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.

Technical description

Boiler in hot water anti-cycle mode

Engineer required

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

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