How much does it cost to fix boiler error code Casting Thermistor Fault?

Typical repair cost for the boiler Casting Thermistor Fault fault is £90-180 including labour.

Casting Thermistor Fault High

Boiler Fault Code Casting Thermistor Fault

Also written as CASTINGTHERMISTORFAULT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Casting Thermistor Fault appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has detected a problem with a temperature sensor on the main internal heat exchanger, causing it to shut down for safety. (As reported on Potterton Performa SL HE 9 2)

Pick your boiler brand for the Casting Thermistor Fault fix

Potterton Casting Thermistor Fault 2 models

Source

Information for the Casting Thermistor Fault 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