Low
S.04 on Vaillant ecoTEC plus Aquaplus

Your boiler is currently operating normally as it is in the process of lighting the flame to provide heating for your home.

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

Burner ignited (heating operation)

Engineer required

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

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Related fault codes

S.00View →S.02View →S.03View →

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