Low
d.09 on Vaillant ecoFIT Pure 412

Your boiler is simply displaying the target temperature currently requested by your room thermostat to confirm it is receiving the signal correctly.

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

Heating flow set target temperature that is set on the eBUS room thermostat

Engineer required

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

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