Low
S.11 on Vaillant Ecomax Condensing 600/800 series

Your boiler is currently operating normally to heat your hot water, so it is simply showing you what stage of the heating cycle it is in.

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

Pump and fan running (hot water 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.10View →

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