BoilerFaultCodes F49 High
Boiler Fault Code F49
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F49 appears across 2 boiler brands and 14 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has lost communication with its external controls like your thermostat because there is an electrical problem with the wiring connecting them. (As reported on Glow-worm Ultracom 24cx 30cx)
Pick your boiler brand for the F49 fix
Source
Information for the F49 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026