Low
d.66 on Vaillant ecoFIT Pure 418

Your boiler is notifying you that it has pre-heated the internal components so that your hot water arrives at your taps more quickly.

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

DIY fix possible

No action is required as this is an advisory status message rather than a breakdown.If you wish to save energy, you can turn the 'Comfort' or 'Pre-heat' mode off via the main control dial.Check your user manual to adjust the hot water temperature settings if it feels too hot.

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