Low
d.07 on Vaillant ecoTEC Plus 840

This code is simply an information display showing the temperature setting currently requested for your hot water tank rather than 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

Set target temperature for the domestic hot water cylinder: Current value

Engineer required

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

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