Medium
d.13 on Vaillant ecoTEC plus Aquaplus

Your boiler is struggling to detect or activate the small pump responsible for moving hot water around your house, meaning you might notice a delay in getting hot water at your taps.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

DHW circulation pump (external)

Engineer required

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

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