Medium
d.13 on Vaillant Ecomax Condensing 600/800 series

Your boiler has detected an issue with an add-on pump responsible for moving water through your heating system.

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

External circulation pump when fitted (ecoMAX 835)

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.14View →F.22View →

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