BoilerFaultCodes Circulation LOCKOUT High
Boiler Fault Code Circulation LOCKOUT
Also written as CIRCULATIONLOCKOUT — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Circulation LOCKOUT 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 has detected that hot water isn't moving around your radiators or pipes properly and has shut itself down to prevent overheating. (As reported on Potterton Suprima HE)
Pick your boiler brand for the Circulation LOCKOUT fix
Source
Information for the Circulation LOCKOUT 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