Low
d.58 on Vaillant ecoTEC Plus 840

Your boiler is currently checking its settings for solar-heated water to ensure it meets safety standards for preventing bacteria growth.

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

Solar circuit reheating: 0=Boiler's Legionella protection function deactivated, 3=Hot water activated (min. target value 60°C)

Engineer required

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

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