Low
d.16 on Vaillant ecoTEC Plus 65

Your boiler is correctly receiving a signal from your thermostat that the heating is currently turned off.

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

Check your wall-mounted thermostat or smart app settings to ensure they are set to 'on' or 'active'Increase the target temperature on your room thermostat to see if the boiler status changes to 'on'Check batteries in your wireless thermostat unit if applicable

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