Boiler Fault Code FA 364

Also written as FA364 — same fault.

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

Fault code FA 364 appears across 1 boiler brand and 11 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 its internal safety checks detected that a gas valve isn't closing properly, which could lead to a small amount of gas escaping into the unit. (As reported on Worcester Bosch 35 RSF)