How much does it cost to fix boiler error code Lights Flash On Flash?

Typical repair cost for the boiler Lights Flash On Flash fault is £250-400 including labour.

Lights Flash On Flash High

Boiler Fault Code Lights Flash On Flash

Also written as LIGHTSFLASHONFLASH — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Lights Flash On Flash appears across 2 boiler brands and 5 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning The internal computer board inside your boiler has developed a fault and is failing to send the correct signals to start your heating and hot water. (As reported on Potterton Promax 15/2 HE Plus)

Pick your boiler brand for the Lights Flash On Flash fix

Baxi Lights Flash On Flash 2 models Potterton Lights Flash On Flash 3 models

Source

Information for the Lights Flash On Flash 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