BoilerFaultCodes F 05 High
Boiler Fault Code F 05
Also written as F05 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F 05 appears across 1 boiler brand and 4 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is struggling to accurately measure the temperature of the water returning to it, so it has stopped working as a safety precaution until the faulty sensor is replaced. (As reported on Ideal Logic+ Heat)
Pick your boiler brand for the F 05 fix
Source
Information for the F 05 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