Low
d.05 on Vaillant Thermocompact

Your boiler is simply displaying the current temperature setting for the water flowing to your radiators, which is a normal status report rather than a fault.

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

This is a status code, not an error.Press the 'i' button on your boiler display to return to the standard operating view.No further action is required as the boiler is operating normally.

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