High
Lock-out (light on) on Grant Vortex Eco

Your boiler has stopped itself from running as a safety precaution because the fuel failed to ignite properly.

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

Burner not starting - fuel and electricity supplies present. Press the reset button on the burner control box.

From this model's manual
Verified against the Grant Vortex Eco External Floor Standing Installation And Servicing Manual DOC81 Rev02 November 2008 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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