How much does it cost to fix boiler error code Yellow | On every 0.5 second?

Typical repair cost for the boiler Yellow | On every 0.5 second fault is £0-80 including labour.

Yellow | On every 0.5 second Low

Boiler Fault Code Yellow | On every 0.5 second

Also written as YELLOWONEVERY05SECOND — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Yellow | On every 0.5 second appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is currently in a manual testing mode often used by engineers and is not experiencing a functional fault. (As reported on Vokera Compact HE)

Pick your boiler brand for the Yellow | On every 0.5 second fix

Vokera Yellow | On every 0.5 second 1 model

Source

Information for the Yellow | On every 0.5 second 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