Low
d.06 on Vaillant ecoTEC Plus 840

Your boiler is simply displaying the temperature setting currently programmed for your hot water, rather than indicating a system fault.

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

Hot water set target temperature: Current value (Combination unit only)

Engineer required

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

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