How much does it cost to fix boiler error code Red LED on only?

Typical repair cost for the boiler Red LED on only fault is £120-250 including labour.

Red LED on only High

Boiler Fault Code Red LED on only

Also written as REDLEDONONLY — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Red LED on only appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has stopped working because it is not receiving the correct electrical signal or has blown an internal fuse required to power its main components. (As reported on Potterton Prima 30B)

Pick your boiler brand for the Red LED on only fix

Potterton Red LED on only 2 models

Source

Information for the Red LED on only 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