BoilerFaultCodes E.04 – .08 High
Boiler Fault Code E.04 – .08
Also written as E0408 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code E.04 – .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 has shut down because it has detected it is getting too hot, likely due to a lack of water flow or a sensor failure. (As reported on Baxi 200 / 400 Combi)
Pick your boiler brand for the E.04 – .08 fix
Source
Information for the E.04 – .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