Low
d.7 on Vaillant ecoMAX

Your boiler is simply reporting the current temperature setting selected for its internal hot water storage feature.

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 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

This is an information code rather than a fault.If you wish to switch off the 'Warmstart' feature, locate the 'eco' or hot water settings button on your boiler's control panel.Toggle the setting to 'off' or adjust the temperature dial to your preference to clear this status display.

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