BoilerFaultCodesYour boiler is temporarily pausing its heating cycle to prevent it from switching on and off too frequently after a short period of use.
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: Burner lock after recharging/heat retention (cycle suppression)
What causes this fault?
This status occurs when your boiler has reached the required temperature too quickly and needs to pause for a few minutes before firing again. It usually happens because the heat has nowhere to go, often because your radiators are already warm or several thermostatic radiator valves have closed at once. By locking the burner temporarily, the boiler prevents unnecessary wear and tear caused by 'short cycling'.
This is more common in spring and autumn when the weather is milder and your home doesn't require the boiler to run at its full heat capacity for long periods.
DIY fix possible
Wait for 5 to 10 minutes for the boiler to complete its anti-cycling delay periodCheck that your room thermostat is set to the desired temperatureEnsure radiators are turned on to allow heat to dissipate
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