Low
D.066 on Vaillant ecoTEC Plus 832

Your boiler is signalling that the 'warm start' feature, which keeps a small amount of water pre-heated for faster hot water taps, is currently active or adjusting.

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.

What the manual says

Manufacturer manual

Warmstartactivation

From this model's manual
Verified against the Vaillant Ecotec Plus installation & service manual, page 75.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Navigate to the boiler's menu settingsLocate the 'Warmstart' or 'Comfort' mode optionToggle the setting to 'Off' if you do not require instant hot water, or 'On' if you wish to use the feature

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