How much does it cost to fix boiler error code 9?

Typical repair cost for the boiler 9 fault is £180-450 including labour.

9 High

Boiler Fault Code 9

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code 9 appears across 3 boiler brands and 3 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has shut down because the internal fan is spinning faster than the system allows, preventing the boiler from safely managing the gas flame. (As reported on Unical Alkon R 28 HE)

Pick your boiler brand for the 9 fix

Remeha 9 1 model Unical 9 1 model Worcester Bosch 9 1 model

Source

Information for the 9 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