d.41 Low

Boiler Fault Code d.41

Also written as D41 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code d.41 appears across 3 boiler brands and 45 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is displaying the current temperature of the water returning from your radiators rather than showing an error; this is an informational status code and not a fault. (As reported on Vaillant ecoFIT Pure 435)

Pick your boiler brand for the d.41 fix

Glow-worm d.41 6 models Heatline d.41 7 models Vaillant d.41 32 models

Source

Information for the d.41 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 31 August 2026