High
Lockout button lit on Grant Vortex 15-20

Your boiler has detected an issue preventing it from lighting and has shut down for safety; it needs a manual reset to try and start again.

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 Lockout. Press ‘Lockout’ button to reset burner. If burner does not fire – refer to Section 12.4 Burner Fault Finding.

From this model's manual
Verified against the Grant Vortex Pro Internal Combi Installation Servicing Instructions DOC88 Rev00 May 2012 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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