Low
YELLOW LED LIGHT on Pro ProCombi 100HE

Your boiler is currently running in a professional testing mode used by engineers to check emissions, which is why the yellow light is showing.

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

Chimney sweeper cycle active.

From this model's manual
Verified against the Pro Procombi 100he 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

Locate the selector dial on the front of the boiler control panel.Turn the dial away from the 'test' or 'chimney' position back to the 'reset' or 'on' position.Wait for the yellow light to turn off and the boiler to return to normal operation.

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