Low
d.64 on Vaillant ecoFIT Pure 835

Your boiler is taking longer than expected to light the flame, which could lead to an intermittent loss of heating and hot water if left unaddressed.

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

Average burner ignition time

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 →d.65View →

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