Low
d.08 on Vaillant ecoTEC plus Aquaplus

Your boiler is receiving a signal from your thermostat or smart controller to turn on the heating, so it is simply working as intended.

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

External controls heat demand

Engineer required

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

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Related fault codes

d.00View →d.01View →

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