Low
d.7 on Vaillant Ecomax Condensing 600/800 series

Your boiler is currently displaying its warm water preset status rather than an active fault, indicating your hot water pre-heating feature is enabled.

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

Warmstart temperature setting (ecoMAX 800)

From this model's manual
Verified against the Vaillant Ecomax Condensing 600 800 Series installation & service manual, page 47.
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 the digital display to the d.7 settingObserve the value shownIdentify if the setting is relevant to your specific boiler usageConsult the user manual to see if a simple adjustment is permitted

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