Low
S.13 on Vaillant aquaPLUS

Your boiler is currently trying to light its internal burner to provide you with hot water.

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

Ignition sequence (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.03View →S.11View →S.14View →

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