Low
S.10 on Vaillant Ecomax Condensing 600/800 series

Your boiler is correctly responding to a request to heat your domestic hot water and is operating normally.

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

Hot water demand (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.11View →

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