F11 High

Boiler Fault Code F11

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code F11 appears across 6 boiler brands and 44 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler's main internal computer is having trouble communicating with its electronic components, meaning it cannot process instructions to provide heat. (As reported on Vaillant ecoMAX Pro 28E)

Pick your boiler brand for the F11 fix

Ferroli F11 13 models Glow-worm F11 12 models Heatline F11 8 models Intergas F11 3 models Saunier Duval F11 6 models Vaillant F11 2 models

Source

Information for the F11 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