Low
S.03 on Vaillant ecoTEC plus Aquaplus

Your boiler is currently trying to light the flame to start heating your home, which is a normal part of its automatic start-up process.

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

Ignition sequence (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

F.27View →F.28View →F.29View →

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