Adj Low

Boiler Fault Code Adj

Also written as ADJ — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code Adj 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 undergoing an automatic internal calibration process, which usually happens during setup or after specific adjustments. (As reported on Vokera Vision Combi 25C / 30C)

Pick your boiler brand for the Adj fix

Vokera Adj 3 models

Source

Information for the Adj 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