How much does it cost to fix boiler error code GM012?

Typical repair cost for the boiler GM012 fault is £150-£250 including labour.

GM012 High

Boiler Fault Code GM012

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code GM012 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 an internal communication error where a signal meant to confirm it is safe to operate is not being received, causing it to shut down for your protection. (As reported on Baxi 400 Combi 2)

Pick your boiler brand for the GM012 fix

Baxi GM012 1 model

Source

Information for the GM012 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 7 July 2026