High
Burner reset light red flash (0.5s) on Grant Vortex Blue

Your boiler has stopped because it thinks it sees a flame when there shouldn't be one, which is usually caused by a dirty sensor or an incorrect air-to-fuel mix.

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.

What the manual says

Manufacturer manual

Lockout: false flame signal during operation — badly adjusted burner

From this model's manual
Verified against the Grant Vortexblue Doc0131 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 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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Related fault codes

Lockout - Solid RedView →Flash 1.0sView →

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