BoilerFaultCodes db Low
Boiler Fault Code db
Also written as DB — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code db appears across 1 boiler brand and 7 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has lost its connection to one of the temperature sensors used to control your heating, though it will likely keep running in a basic backup mode. (As reported on Viessmann Vitodens 333)
Pick your boiler brand for the db fix
Source
Information for the db 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