Low
S.03 on Vaillant ecoTEC plus System

Your boiler is currently working correctly and is in the process of lighting the flame to begin heating 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

Heating mode: Burner ignition

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.02View →S.04View →

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