High
HW light On (flashing) on Worcester Bosch 24CDi BF

Your boiler has sensed that the water inside it is getting too hot and has automatically switched itself off to prevent damage.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Over temperature shut-down if water temperature 8°C above set value. Ten second wait.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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