LED 1: Off, LED 2: On Low

Boiler Fault Code LED 1: Off, LED 2: On

Also written as LED1OFFLED2ON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

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

Most common meaning Your boiler is operating normally and performing its job of heating water as expected. (As reported on Halstead Buckingham 4)

Pick your boiler brand for the LED 1: Off, LED 2: On fix

Halstead LED 1: Off, LED 2: On 1 model

Source

Information for the LED 1: Off, LED 2: On 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