How much does it cost to fix boiler error code 1 2.?

Typical repair cost for the boiler 1 2. fault is £90-180 including labour.

1 2. High

Boiler Fault Code 1 2.

Also written as 12 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 1 2. appears across 3 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's internal electronic protection has triggered and the unit has completely lost power due to a failed internal fuse. (As reported on Remeha Quinta Ace 25)

Pick your boiler brand for the 1 2. fix

Glow-worm 1 2. 1 model Remeha 1 2. 5 models Saunier Duval 1 2. 2 models

Source

Information for the 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