High
Lock-out (Red neon) on Grant Vortex

Your boiler has stopped working because the flame inside failed to light or stay on.

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 has failed to ignite or flame has been lost. Press the reset button on the burner control box if it is lit.

From this model's manual
Verified against the Grant/Grant Vortex 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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All 33 fault codes on the Vortex

Seeing a different code? Every code this model can display, in one place.

101215/2620.023.026.026/3631.536.036/4641.546.046/5852.058.058/7064.070.0GE45/90GEB90GEB200GK90GK90SGK200GK200SGTH90GTH200GTV90GTV200GWB90GWB200Lock-out

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