BoilerFaultCodes bd Medium
Boiler Fault Code bd
Also written as BD — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code bd 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 communication with your remote room thermostat or heating controller for the second heating circuit. (As reported on Viessmann Vitodens 333)
Pick your boiler brand for the bd fix
Source
Information for the bd 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