BoilerFaultCodes No Switched Live High
Boiler Fault Code No Switched Live
Also written as NOSWITCHEDLIVE — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code No Switched Live 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 not receiving the electrical signal from your thermostat or programmer telling it to turn on. (As reported on Potterton Promax 15 & 24)
Pick your boiler brand for the No Switched Live fix
Source
Information for the No Switched Live 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