L8 High

Boiler Fault Code L8

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code L8 appears across 2 boiler brands and 13 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler's internal computer has forgotten its settings or has developed a technical communication error, meaning it cannot safely control the heating process. (As reported on Ideal Logic+ System)

Pick your boiler brand for the L8 fix

Source

Information for the L8 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