Emergency
FALSE FLAME LOCKOUT on Johnson Starley Quantec C

Your boiler has detected a flame inside when the system is supposed to be turned off, which is a safety mechanism triggered to prevent incorrect operation.

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

Boiler detects flame when it should not, or issues with flame sensor electrode

From this model's manual
Verified against the Johnson Starley Quantec C installation & service manual.
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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