BoilerFaultCodes CH flow NTC sensor defective. High
Boiler Fault Code CH flow NTC sensor defective.
Also written as CHFLOWNTCSENSORDEFECTIVE — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code CH flow NTC sensor defective. 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 is struggling to read its own internal water temperature because a sensor has stopped working correctly, which will likely prevent it from heating your home. (As reported on Worcester Bosch 532 / 537 / 542)
Pick your boiler brand for the CH flow NTC sensor defective. fix
Source
Information for the CH flow NTC sensor defective. 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 7 July 2026