Low
d.05 on Vaillant Turbomax Plus 828 E

This code is simply showing you the current temperature setting for your heating water, not indicating an actual fault with the boiler.

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

Flow temperature setting °C

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

Check your boiler display to confirm it is showing a standard temperature reading rather than a flashing error codeAdjust your heating temperature dial on the front panel if you wish to change the current settingRefer to your user manual to confirm the boiler is operating normally in its intended mode

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