Low
S.05 on Vaillant ecoTEC exclusive

Your boiler is simply finishing its normal cooling process after the heating has turned off, so there is no need to worry.

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

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

S.04View →S.06View →

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