How much does it cost to fix boiler error code 406?

Typical repair cost for the boiler 406 fault is £320-£550 including labour.

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Boiler Fault Code 406

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 406 appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has experienced a direct failure of its main internal computer brain and cannot control the heating or hot water safely. (As reported on Ideal Response SE)

Pick your boiler brand for the 406 fix

Ideal 406 2 models

Source

Information for the 406 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