Low
S.04 on Vaillant aquaPLUS

Your boiler is currently working as expected and has successfully lit its flame to provide heating for your home.

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

Burner ignited (heating operation)

DIY fix possible

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

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Related fault codes

S.00View →S.03View →S.07View →

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