Low
S.10 on Vaillant aquaPLUS

Your boiler is operating normally and is currently heating up your hot water because it has detected a demand.

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)

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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Related fault codes

S.11View →S.13View →S.14View →

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