How much does it cost to fix boiler error code 012?

Typical repair cost for the boiler 012 fault is £80-150 including labour.

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Boiler Fault Code 012

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 012 appears across 1 boiler brand and 7 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 that it is running out of water inside its internal system, which prevents it from heating your home safely. (As reported on Navien NCB)

Pick your boiler brand for the 012 fix

Navien 012 7 models

Source

Information for the 012 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