BoilerFaultCodes GM008 High
Boiler Fault Code GM008
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code GM008 appears across 1 boiler brand and 1 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 detect the flame needed to heat your water and home, which is likely due to a sensor or ignition issue. (As reported on Baxi 400 Combi 2)
Pick your boiler brand for the GM008 fix
Source
Information for the GM008 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