Low
305 on Worcester Bosch 1000

Your boiler has detected that it is running the hot water cycle too frequently and is temporarily pausing to prevent overheating or unnecessary wear.

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

What causes this fault?

Heat exchanger cycle mode

Engineer required

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

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Related fault codes

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