Low
d.08 on Vaillant ecoFIT Pure 412

This code is not actually an error; it simply displays the current status of your room thermostat to let you know if your heating is being requested to turn on or off.

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 230V thermostat (0=Room thermostat open, 1=Room thermostat closed)

Engineer required

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

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