BoilerFaultCodes D.167 Medium
Boiler Fault Code D.167
Also written as D167 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code D.167 appears across 1 boiler brand and 3 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 with your hot water cylinder, which may mean you will have no hot water until the connection is restored. (As reported on Vaillant ecoTEC plus)
Pick your boiler brand for the D.167 fix
Source
Information for the D.167 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