High
Failure at point O on Worcester Bosch 24CDi BF

Your boiler continues to fire even after you have turned off your hot water tap, which can cause the internal temperature to rise too high.

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

Burner does not shut down immediately when the tap is turned off. Check flow switch and main driver board.

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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