How much does it cost to fix boiler error code 0A43?

Typical repair cost for the boiler 0A43 fault is £120-220 including labour.

0A43 High

Boiler Fault Code 0A43

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 0A43 appears across 1 boiler brand and 3 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is currently unable to read the water temperature correctly because of a faulty internal sensor connection, which has caused it to stop heating your home as a safety precaution. (As reported on Alpha Pro Tec Plus)

Pick your boiler brand for the 0A43 fix

Alpha 0A43 3 models

Source

Information for the 0A43 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