High
Red L.E.D. D on Ariston Excalibur

Your boiler has failed to light the flame and has locked itself out for safety.

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

Ignition failure (lockout). If, after approximately 10 seconds, the burner has not ignited, the boiler safety devices will shut off the gas and the red L.E.D. D illuminates.

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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