High
Burner lock-out on Grant Vortex Eco External Floor Standing

Your boiler has detected a temporary issue with the burner and has safely shut itself down to prevent any damage.

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

If there is a burner malfunction, a built-in safety circuit switches the burner off and the 'Lock-out' reset button on the burner will light. Usually such malfunctions are short lived and pressing the red reset button will restore normal operation.

From this model's manual
Verified against the Grant Vortex Eco 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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