Red L.E.D. D High

Ariston Red L.E.D. D Fault Code

Also written as REDLEDD — same fault.

The Ariston Red L.E.D. D fault code means: your boiler has failed to light the flame and has locked itself out for safety.. It appears on 1 Ariston model in our database.

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.
Typical repair cost £120-280 (including labour)

DIY fix possible

Check if other gas appliances in your home (like a hob) are working to ensure gas supply is active.Check your gas meter to ensure it has credit if you use a prepay meter.Press the 'Reset' button on the control panel to attempt a restart.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

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Ariston models that show the Red L.E.D. D fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ariston Red L.E.D. D fault code information on this page is sourced and cross-checked against the official Ariston service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026