High
F7 on Worcester Bosch Danesmoor

Your boiler thinks it can see a flame when it shouldn't be running, which is likely caused by moisture or a sensor error.

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

Flame detected even though the appliance is switched off – check the electrode assembly is dry and the pcb and flue are clear.

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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