BoilerFaultCodes EE5566 High
Boiler Fault Code EE5566
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code EE5566 appears across 1 boiler brand and 3 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 the signal from the sensor that monitors the temperature of the water being sent to your radiators, which prevents it from heating your home safely. (As reported on Ariston Micro Condens)
Pick your boiler brand for the EE5566 fix
Source
Information for the EE5566 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 7 July 2026