BoilerFaultCodes H.01 – .08 High
Boiler Fault Code H.01 – .08
Also written as H0108 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code H.01 – .08 appears across 1 boiler brand and 24 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is overheating because water isn't moving through the system quickly enough to be cooled down. (As reported on Baxi 200 / 400 Combi)
Pick your boiler brand for the H.01 – .08 fix
Source
Information for the H.01 – .08 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