BoilerFaultCodes D.44 High
Boiler Fault Code D.44
Also written as D44 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code D.44 appears across 1 boiler brand and 6 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is having trouble managing its flame correctly and has shut down as a safety precaution. (As reported on Vaillant ecoTEC plus Regular)
Pick your boiler brand for the D.44 fix
Source
Information for the D.44 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 27 April 2026