Lights: Flash Off Flash High

Boiler Fault Code Lights: Flash Off Flash

Also written as LIGHTSFLASHOFFFLASH — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code Lights: Flash Off Flash appears across 2 boiler brands and 8 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is receiving an insufficient amount of electricity to operate correctly, which is usually caused by an issue with your home's power supply rather than a fault within the boiler itself. (As reported on Potterton Promax Heat Only)

Pick your boiler brand for the Lights: Flash Off Flash fix

Baxi Lights: Flash Off Flash 3 models Potterton Lights: Flash Off Flash 5 models

Source

Information for the Lights: Flash Off Flash 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