Low
D.64 on Vaillant Atmomax

Your boiler is struggling to light consistently, meaning it is taking longer than usual to ignite the gas and start heating.

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 ignition times

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.65View →

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