How much does it cost to fix boiler error code F6?

Typical repair cost for the boiler F6 fault is £90-180 including labour.

F6 Low

Boiler Fault Code F6

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code F6 appears across 7 boiler brands and 50 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 connection with the sensor that monitors the outdoor temperature, making it difficult for the system to adjust its heat settings efficiently. (As reported on Ideal Logic Combi C24 C30 C35)

Pick your boiler brand for the F6 fix

Ferroli F6 2 models Glow-worm F6 5 models Heatline F6 10 models Ideal F6 17 models Keston F6 8 models Saunier Duval F6 6 models Vaillant F6 2 models

Source

Information for the F6 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