BoilerFaultCodes AL 88 High
Boiler Fault Code AL 88
Also written as AL88 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code AL 88 appears across 1 boiler brand and 6 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 detected a serious hardware failure and has shut itself down to protect its electrical components. (As reported on Sime Halstead Trio)
Pick your boiler brand for the AL 88 fix
Source
Information for the AL 88 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