Low
S.10 on Vaillant ecoTEC Pro 30

Your boiler is simply letting you know that it is currently busy heating water for your taps or shower.

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 requirement via flow sensor

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.00View →S.11View →

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