Medium
d.12 on Vaillant ecoTEC plus Aquaplus

Your boiler is signalling that the small pump responsible for moving hot water to your taps or storage cylinder is not receiving the expected electrical signal.

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 pump - status

Engineer required

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

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Related fault codes

d.11View →d.13View →

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