Low Warning
D.64 on Vaillant ecoTEC plus Regular

Your boiler is taking longer than expected to light the flame, which is currently an advisory warning about its operation.

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

What causes this fault?

This fault occurs when the boiler's internal computer notices that the burner is taking consistently longer than usual to establish a stable flame. The most common reasons are that the sensors used to detect the flame are becoming dirty or worn, or the gas valve is struggling to provide the correct amount of fuel during the starting sequence.

Engineer required

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

Find a Gas Safe engineer
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Related fault codes

F.28View →F.29View →D.65View →

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