How much does it cost to fix boiler error code EE9999?

Typical repair cost for the boiler EE9999 fault is £250-450 including labour.

EE9999 High

Boiler Fault Code EE9999

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code EE9999 appears across 1 boiler brand and 4 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler's main computer control panel is experiencing a general communication error, preventing it from starting safely. (As reported on Ariston Genus 24 MFFI)

Pick your boiler brand for the EE9999 fix

Ariston EE9999 4 models

Source

Information for the EE9999 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