How much does it cost to fix boiler error code 30c?

Typical repair cost for the boiler 30c fault is £90-160 including labour.

30c High

Boiler Fault Code 30c

Also written as 30C — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 30c appears across 1 boiler brand and 10 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has likely detected a problem with the temperature sensor or its wiring, meaning it cannot accurately gauge how hot the water is. (As reported on Biasi Parva 24S)

Pick your boiler brand for the 30c fix

Biasi 30c 10 models

Source

Information for the 30c 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