High
FAULT POINT F on Worcester Bosch Greenstar 15sbi

Your boiler has identified an unusual temperature reading or a general internal disagreement, meaning it has safely shut itself down 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

Other faults not covered by above (e.g. water temperature too hot or too low)

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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