Low
d.65 on Vaillant Home System

Your boiler is displaying a status code showing how long the burner is taking to fire up, which usually indicates the system is working harder than normal to ignite.

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.

Technical description

Maximum burner ignition time: Current value in seconds

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

F.28View →F.29View →d.64View →

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