BoilerFaultCodes Overheat indicator High
Boiler Fault Code Overheat indicator
Also written as OVERHEATINDICATOR — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Overheat indicator 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 has switched itself off because it has become too hot internally, often due to a temporary blockage or a circulation issue. (As reported on Baxi Promax Ultra)
Pick your boiler brand for the Overheat indicator fix
Source
Information for the Overheat indicator 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