BoilerFaultCodes 4-E2 High
Boiler Fault Code 4-E2
Also written as 4E2 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 4-E2 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has detected a tempereature sensor reading that is outside of its normal range, likely due to a faulty sensor or a communication error between parts. (As reported on Worcester Bosch Greenstar 2000)
Pick your boiler brand for the 4-E2 fix
Source
Information for the 4-E2 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