Low
d.66 on Vaillant ecoTEC plus System

This code simply indicates whether the comfort setting that keeps your tap water pre-warmed is currently turned 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

Activation of the warm start function for hot water: off=Function deactivated, on=Function activated

DIY fix possible

Locate the menu button on your boiler displayNavigate to the 'Comfort' or 'Warmstart' settingsSelect 'On' or 'Off' based on your personal heating preference

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