High
Fast flash on Grant Vortex 15-20

Your boiler has failed to light the burner and is currently locked out to prevent any issues.

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.

Technical description

Burner indicator flashing fast (Refer to Section 12.2 (C))

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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Related fault codes

LockoutView →Burner lock-outView →

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