Low
S.23 on Vaillant aquaPLUS

Your boiler is currently heating up the internal hot water storage tank so it is ready for you to use.

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 (store charging)

DIY fix possible

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

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Related fault codes

S.20View →S.24View →

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