D.046 Low

Boiler Fault Code D.046

Also written as D046 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code D.046 appears across 1 boiler brand and 4 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is currently running a background check to confirm the internal pump is circulating water correctly throughout your heating system. (As reported on Vaillant ecoTEC Pro)

Pick your boiler brand for the D.046 fix

Vaillant D.046 4 models

Source

Information for the D.046 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 7 July 2026