59 High
Boiler Fault Code 59
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 59 appears across 2 boiler brands and 18 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has stopped working because it cannot accurately measure the temperature of the water leaving the unit, usually due to a fault in a sensor or its wiring. (As reported on Viessmann Vitodens 200)
Pick your boiler brand for the 59 fix
Source
Information for the 59 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