Low
S.04 on Vaillant Combi Compact 242EB

Your boiler is operating normally and is currently firing the burner to provide central heating to 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

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.01View →S.03View →S.07View →S.08View →

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