How much does it cost to fix boiler error code U 1.2?

Typical repair cost for the boiler U 1.2 fault is £120-200 including labour.

U 1.2 High

Boiler Fault Code U 1.2

Also written as U12 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code U 1.2 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 stopped working because a small protective device inside the electrical system has failed, cutting off the power needed to operate the internal controls. (As reported on Ideal Imax W)

Pick your boiler brand for the U 1.2 fix

Ideal U 1.2 1 model

Source

Information for the U 1.2 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