Low
d.64 on Vaillant Home System

Your boiler is displaying an information message showing how long it typically takes for the burner to light, rather than a technical fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Average burner ignition time: Current value in seconds

From this model's manual
Verified against the Vaillant Home System 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.

DIY fix possible

No action is required as this is an advisory status codePress the 'Back' or 'Menu' button to return to the main displayMonitor the boiler for any actual fault codes starting with 'F'

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d.65View →d.67View →

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