High
RED steady ON on Grant Vortex 20-26

Your boiler has stopped working because it failed to light the fuel inside, likely due to a blockage in the oil supply or a dirty sensing component.

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 flame is not detected after the safety time. UV sensor defective or dirty; Oil valve defective or dirty; Faulty ignition transformer; Badly regulated burner; Oil fuel not present.

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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