How much does it cost to fix boiler error code 3 flashes red?

Typical repair cost for the boiler 3 flashes red fault is £150-300 including labour.

3 flashes red High

Boiler Fault Code 3 flashes red

Also written as 3FLASHESRED — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 31 August 2026

Fault code 3 flashes red appears across 1 boiler brand and 5 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 light or stay lit, which means it has stopped producing heat and hot water as a safety precaution. (As reported on Baxi 800 Heat)

Pick your boiler brand for the 3 flashes red fix

Baxi 3 flashes red 5 models

Source

Information for the 3 flashes red 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 31 August 2026