High
Lock-out on Grant Vortex Eco External Wall Hung

Your boiler has stopped trying to fire up, likely because it couldn't detect a flame, and requires a manual reset to try starting 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

The 'Lock-out' reset button lights if the burner does not light. Wait for about 45 seconds then press the reset button to restart the ignition process.

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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