23 High

Boiler Fault Code 23

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code 23 appears across 19 boiler brands and 82 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 the temperature sensor that monitors the water returning to the unit, causing it to stop running for safety. (As reported on Intergas Combi Compact ECO RF)

Pick your boiler brand for the 23 fix

Alpha 23 18 models Atmos 23 4 models Baxi 23 6 models Biasi 23 4 models Chaffoteaux 23 5 models Daikin 23 3 models Ferroli 23 4 models Gledhill 23 1 model Heatline 23 3 models Ideal 23 4 models Intergas 23 11 models Main 23 2 models Potterton 23 3 models Saunier Duval 23 3 models Sime 23 2 models Unical 23 2 models Vaillant 23 1 model Vokera 23 5 models Worcester Bosch 23 1 model

Source

Information for the 23 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