Low
d.07 on Vaillant Turbomax Plus 824/828E

Your boiler is simply reporting the current temperature setting of the 'warm start' feature, which keeps a small amount of water pre-heated for faster taps.

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

1. Vantage hot water temperature (not applicable) 2. Warmstart temperature setting (applies to turboMAX plus only)

From this model's manual
Verified against the Vaillant Turbomax Plus 824 828e installation & service manual, page 39.
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

Locate the 'Warmstart' button on your boiler control panel.Press the button to toggle the feature off if you wish to save energy, or leave it on if you prefer instant hot water.Observe the display to see if it reverts to the normal operating temperature.

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