How much does it cost to fix boiler error code F78?

Typical repair cost for the boiler F78 fault is £90-180 including labour.

F78 High

Boiler Fault Code F78

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code F78 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 lost communication with its external controls or internal wiring kit, preventing it from heating your home. (As reported on British Gas 330+)

Pick your boiler brand for the F78 fix

British Gas F78 1 model

Source

Information for the F78 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 7 July 2026