Low
S.05 on Vaillant ecoTEC plus Aquaplus

Your boiler is simply performing a routine cooling-down process after your heating has been running, which is completely normal operation.

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

Fan and water pump over run (heating operation)

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.00View →S.02View →S.04View →

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