Low
S.05 on Vaillant Home System

Your boiler is simply taking a short break to circulate water and cool down internal parts after a period of 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: Pump/fan overrun

DIY fix possible

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

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Related fault codes

S.07View →S.08View →

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