Low Information
S.28 on Glow-worm Ultracom sxi

Your boiler is taking a short, programmed break to prevent it from turning on and off too frequently, which helps protect the internal components from wear and tear.

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

Anticycling period

What causes this fault?

This occurs when your boiler reaches its target temperature too quickly and shuts down to prevent 'short-cycling,' which wastes energy and puts stress on the components. It usually happens because the heat produced by the boiler cannot be moved away fast enough, often due to thermostatic radiator valves closing as rooms get warm. The boiler is simply waiting for the system water to cool down slightly before it is safe and efficient to fire up again.

This is more common during the 'shoulder' seasons of spring and autumn, when the weather is mild and your radiators don't need the boiler's full heat output to keep the house warm.

DIY fix possible

Wait 5 to 15 minutes for the countdown timer to finishCheck that your room thermostat is turned up higher than the current room temperatureEnsure your radiator valves are open to allow heat to dissipate

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