How much does it cost to fix boiler error code FLASH OFF ON?

Typical repair cost for the boiler FLASH OFF ON fault is £100-280 including labour.

FLASH OFF ON High

Boiler Fault Code FLASH OFF ON

Also written as FLASHOFFON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code FLASH OFF ON appears across 2 boiler brands and 28 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has shut down because it has become too hot and needs to be safely reset after cooling down. (As reported on Baxi Solo)

Pick your boiler brand for the FLASH OFF ON fix

Baxi FLASH OFF ON 24 models Potterton FLASH OFF ON 4 models

Source

Information for the FLASH OFF ON 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