How much does it cost to fix boiler error code 4 1 2?

Typical repair cost for the boiler 4 1 2 fault is £120-250 including labour.

4 1 2 High

Boiler Fault Code 4 1 2

Also written as 412 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 4 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 is experiencing a communication fault with a safety sensor, which has caused it to stop working to ensure your protection. (As reported on Ariston HS Premium)

Pick your boiler brand for the 4 1 2 fix

Ariston 4 1 2 1 model

Source

Information for the 4 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