Boiler Fault Code Permanent Live 'On'

Also written as PERMANENTLIVEON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code Permanent Live 'On' 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 currently reporting that it is receiving a constant electrical signal to start heating, which is a normal indicator light used by engineers to check that the internal wiring is receiving power. (As reported on Potterton Ultra 2 50 DV)