Low
YELLOW LED ON every 0.5-secs on Vokera Sabre 25 HE Plus

Your boiler is currently running in a special engineer-only testing mode used to check combustion levels.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

CO function active

From this model's manual
Verified against the Vokera Sabre 25 He Plus installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if the selector dial is accidentally set to the 'CO' or combustion test positionTurn the main selector dial back to the 'Auto' or 'On' positionWait up to 15 minutes for the mode to time out automatically

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