Boiler Fault Code F.24

Also written as F24 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code F.24 appears across 2 boiler brands and 59 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is overheating too quickly because water isn't flowing through the system correctly, often due to low pressure or trapped air. (As reported on Vaillant ecoTEC exclusive)