BoilerFaultCodes Sequence Error High
Boiler Fault Code Sequence Error
Also written as SEQUENCEERROR — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Sequence Error appears across 1 boiler brand and 4 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has become confused while trying to start up and has stopped working for safety reasons. (As reported on Glow-worm Micron 30ff)
Pick your boiler brand for the Sequence Error fix
Source
Information for the Sequence Error 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