E41 High

Boiler Fault Code E41

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code E41 appears across 7 boiler brands and 31 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has sensed an unusual temperature difference between the water leaving it and the water returning, suggesting that water is not circulating through your heating system correctly. (As reported on Ravenheat CSI 120)

Pick your boiler brand for the E41 fix

Alpha E41 5 models Ferroli E41 1 model Keston E41 9 models Potterton E41 1 model Ravenheat E41 9 models Remeha E41 5 models Vokera E41 1 model

Source

Information for the E41 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