Emergency
F7 on Worcester Bosch Highflow CDi

Your boiler is continuing to detect a flame even after it has attempted to turn off, which indicates a serious safety issue that requires immediate professional attention.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

What the manual says

Manufacturer manual

Flame detected after apliance shut off

From this model's manual
Verified against the Worcester Bosch Highflow Cdi installation & service manual, page 54.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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