Low
DEMAND LIGHT ONLY on Worcester Bosch Greenstar 15sbi

Your boiler has reached its target temperature and is simply waiting for your radiators or hot water to cool down before heating up again.

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.

Technical description

It is normal to see only a demand light if the boiler is hot and the burner has temporarily shut off. If boiler is cool, suggests sensor or control board fault.

DIY fix possible

Check that your room thermostat is set high enough to call for heatWait up to 10 minutes for the boiler to complete its anti-cycling delayMonitor the light to see if the burner fires once the water temperature drops

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