BoilerFaultCodes 7b:0 Low
Boiler Fault Code 7b:0
Also written as 7B0 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 7b:0 appears across 1 boiler brand and 5 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 difficulty communicating the correct time over its internal network system, which might affect your heating schedules. (As reported on Viessmann Vitodens 300-W)
Pick your boiler brand for the 7b:0 fix
Source
Information for the 7b:0 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