BoilerFaultCodes 800 / CC Low
Boiler Fault Code 800 / CC
Also written as 800CC — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 800 / CC appears across 1 boiler brand and 2 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 outside temperature, meaning it cannot automatically adjust your heating settings based on the weather. (As reported on Worcester Bosch Greenstar CDi Compact)
Pick your boiler brand for the 800 / CC fix
Source
Information for the 800 / CC 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