Low
d.13 on Vaillant aquaPLUS

Your boiler is reporting a communication issue or a power fault with the external pump that circulates hot water around your taps.

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

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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Related fault codes

d.12View →F.20View →

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