Low
d.46 on Vaillant Ecomax Condensing 600/800 series

Your boiler is struggling to communicate with its outdoor weather sensor, so it is currently ignoring local temperature readings and defaulting to standard operations.

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

Outside–temperature correction (only when VRC 410s is fitted)

Engineer required

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

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Related fault codes

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