Pulse Red (4 flashes) High

Boiler Fault Code Pulse Red (4 flashes)

Also written as PULSERED4FLASHES — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code Pulse Red (4 flashes) 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 trying to start up but is unable to ignite its flame, so it has safely shut down to prevent gas from building up. (As reported on Potterton Envoy Plus)

Pick your boiler brand for the Pulse Red (4 flashes) fix

Potterton Pulse Red (4 flashes) 2 models

Source

Information for the Pulse Red (4 flashes) 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