Boiler Fault Code no. 48

Also written as NO48 — same fault.

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

Fault code no. 48 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has detected that the exhaust gases are becoming dangerously hot and has shut itself down to prevent internal damage. (As reported on Vokera Condexa Pro)