How much does it cost to fix boiler error code LED1 flashing, LED2 on?

Typical repair cost for the boiler LED1 flashing, LED2 on fault is £90-160 including labour.

LED1 flashing, LED2 on High

Boiler Fault Code LED1 flashing, LED2 on

Also written as LED1FLASHINGLED2ON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code LED1 flashing, LED2 on appears across 1 boiler brand and 6 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has detected a problem with the sensor that monitors the temperature of your central heating water, meaning it can't heat your radiators safely. (As reported on Ideal Mini HE)

Pick your boiler brand for the LED1 flashing, LED2 on fix

Ideal LED1 flashing, LED2 on 6 models

Source

Information for the LED1 flashing, LED2 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