Boiler Fault Code d22

Also written as D22 — same fault.

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

Fault code d22 appears across 1 boiler brand and 5 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is simply reminding you that its annual service is due, so it is still safe to use but should be booked in with a professional soon. (As reported on Alpha Evoke 10 / 18)