65 High

Boiler Fault Code 65

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code 65 appears across 9 boiler brands and 18 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is struggling to push air through its system because the internal fan is not spinning at the right speed, causing the unit to stop working for safety reasons. (As reported on Vokera Eclipse)

Pick your boiler brand for the 65 fix

Alpha 65 2 models Biasi 65 4 models ECA 65 1 model Gledhill 65 1 model Ideal 65 3 models Navien 65 1 model Sime 65 4 models Vokera 65 1 model Worcester Bosch 65 1 model

Source

Information for the 65 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