Low
305 on Worcester Bosch Greenstar 8000 Style

Your boiler is temporarily pausing between heat cycles to protect itself and ensure efficient operation, which is a normal behavior rather than a breakdown.

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

Heat exchanger 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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