E33 High

Boiler Fault Code E33

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code E33 appears across 8 boiler brands and 30 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has detected an electrical issue with its power supply or wiring, meaning it cannot safely start the burner. (As reported on Vokera Condexa Pro)

Pick your boiler brand for the E33 fix

Ariston E33 7 models Chaffoteaux E33 1 model Ferroli E33 1 model Johnson Starley E33 8 models Keston E33 9 models Potterton E33 1 model Remeha E33 1 model Vokera E33 2 models

Source

Information for the E33 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