How much does it cost to fix boiler error code RED blinking?

Typical repair cost for the boiler RED blinking fault is £120-220 including labour.

RED blinking High

Boiler Fault Code RED blinking

Also written as REDBLINKING — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code RED blinking appears across 2 boiler brands and 10 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is failing to start because it detects light inside the combustion chamber when it should be completely dark, preventing it from igniting safely. (As reported on Grant Vortex Eco)

Pick your boiler brand for the RED blinking fix

Grant RED blinking 5 models Worcester Bosch RED blinking 5 models

Source

Information for the RED blinking 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