How much does it cost to fix boiler error code 004?

Typical repair cost for the boiler 004 fault is £150-300 including labour.

004 High

Boiler Fault Code 004

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 004 appears across 2 boiler brands and 8 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has encountered a serious internal error that has forced it to shut down for safety reasons and it requires a professional reset. (As reported on Ideal Maximiser SE)

Pick your boiler brand for the 004 fix

Ideal 004 1 model Navien 004 7 models

Source

Information for the 004 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