Low
S.11 on Vaillant ecoTEC

Your boiler is currently performing a standard internal check by running its internal fan to clear out the combustion chamber before it starts 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

Fan running

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.13View →F.32View →

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