How much does it cost to fix boiler error code C?

Typical repair cost for the boiler C fault is £120-250 including labour.

C High

Boiler Fault Code C

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 31 August 2026

Fault code C appears across 9 boiler brands and 14 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is failing to ignite or stay lit, meaning it cannot produce heat or hot water because the flame is not being detected. (As reported on Worcester Bosch 9/14 - 19/24 CBi)

Pick your boiler brand for the C fix

Ariston C 1 model Baxi C 1 model Dimplex C 1 model Halstead C 2 models Ideal C 1 model Main C 2 models Potterton C 1 model Pro C 1 model Worcester Bosch C 4 models

Source

Information for the C 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 31 August 2026