How much does it cost to fix boiler error code E.04 – .12?

Typical repair cost for the boiler E.04 – .12 fault is £120-350 including labour.

E.04 – .12 High

Boiler Fault Code E.04 – .12

Also written as E0412 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code E.04 – .12 appears across 1 boiler brand and 24 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 flame signal when there shouldn't be one, or it is running too hot to operate safely. (As reported on Baxi 200 / 400 Combi)

Pick your boiler brand for the E.04 – .12 fix

Baxi E.04 – .12 24 models

Source

Information for the E.04 – .12 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