Low
GREEN LED ON every 6-secs on Pro ProCombi 100HE

Your boiler is working correctly and is simply in standby mode waiting for you to turn on the heating or hot water.

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

At stand-by with no faults

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

Turn on your central heating thermostat to test functionTurn on a hot water tap to ensure the boiler fires upNo action is required as this is normal operation

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GREEN LED ON every 1-secView →GREEN LED ON CONSTANTView →

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