Low
d.16 on Vaillant ecoFIT Pure 412

This code is simply a status message showing that your room thermostat is currently telling the boiler that it does not need to provide any heating.

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

Status of the 24V room thermostat (off=Heating off, on=Heating on)

DIY fix possible

Turn up your room thermostat to a higher temperatureCheck if the display on your thermostat shows it is calling for heatCheck that your heating programmer or timer is currently set to an 'On' period

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