Low
d.02 on Vaillant Home System

Your boiler is taking a planned break to prevent the system from turning on and off too frequently, which helps save energy and protect internal parts.

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

Maximum burner anti-cycling time in heating mode: 2 to 60 min. Default: 20

DIY fix possible

Wait for the timer to finish (usually 20 minutes) and the boiler will restart automatically.Check that all radiator valves are fully open to allow heat to escape the boiler.Ensure your room thermostat is set high enough to call for heat.

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