Boiler Fault Code No light display when tap on

Also written as NOLIGHTDISPLAYWHENTAPON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026

Fault code No light display when tap on appears across 2 boiler brands 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 detecting when you turn on the hot tap, so it isn't firing up to heat the water. (As reported on Maxol Supacombi HE 24)