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

Typical repair cost for the boiler CF fault is £180-450 including labour.

CF High

Boiler Fault Code CF

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code CF appears across 2 boiler brands and 8 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 communication system has failed, meaning the different electronic parts are no longer talking to each other correctly. (As reported on Viessmann Vitodens 333)

Pick your boiler brand for the CF fix

Viessmann CF 7 models Worcester Bosch CF 1 model

Source

Information for the CF 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