BoilerFaultCodes E218 High
Boiler Fault Code E218
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code E218 appears across 1 boiler brand and 6 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is struggling to accurately measure the temperature of the water being sent to your radiators, so it has safely shut down to prevent overheating. (As reported on Navien NCB)
Pick your boiler brand for the E218 fix
Source
Information for the E218 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