Boiler Fault Code F.14

Also written as F14 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026

Fault code F.14 appears across 3 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 is having trouble communicating with the outdoor sensor that monitors the weather, which can lead to inefficient heating as the system doesn't know how hard it needs to work. (As reported on Viessmann Vitodens 200-W B2KF Combi)