BoilerFaultCodes Preheat neon flashing Low
Boiler Fault Code Preheat neon flashing
Also written as PREHEATNEONFLASHING — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Preheat neon flashing 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 letting you know that the hot water preheat function is active because the control dial is turned up. (As reported on Potterton Performa 28i)
Pick your boiler brand for the Preheat neon flashing fix
Source
Information for the Preheat neon flashing 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