BoilerFaultCodes E 99 High
Boiler Fault Code E 99
Also written as E99 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code E 99 appears across 2 boiler brands 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 has encountered a general internal system error that it cannot automatically resolve, and it requires a professional reset or diagnostic check. (As reported on Warmhaus Enerwa)
Pick your boiler brand for the E 99 fix
Source
Information for the E 99 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