BoilerFaultCodes E85 740 High
Boiler Fault Code E85 740
Also written as E85740 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code E85 740 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is failing to detect a flame, which prevents it from safely igniting and providing you with heating or hot water. (As reported on Potterton Promax 15 & 24)
Pick your boiler brand for the E85 740 fix
Source
Information for the E85 740 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