Low
S.04 on Vaillant Atmomax

Your boiler is currently working as it should and the burner has successfully lit to provide central heating.

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

Heating mode – burner ignited

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.07View →S.08View →

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