BoilerFaultCodes C3 Low
Boiler Fault Code C3
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code C3 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 briefly pausing itself to prevent the system from turning on and off too frequently, which helps protect the internal parts from unnecessary wear. (As reported on Potterton Envoy 30)
Pick your boiler brand for the C3 fix
Source
Information for the C3 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