Your boiler is taking a short, five-minute break to protect itself from turning on and off too frequently.
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: Boiler restart delayed to prevent rapid cycling (max delay time 5 mins).
What causes this fault?
This occurs when your boiler reaches its target temperature too quickly, causing it to shut down briefly to prevent excessive wear and tear on the components. It is often caused by the heat having nowhere to go, such as when all your radiator valves are closed or the pump is struggling to circulate water fast enough. To protect itself, the boiler enters a timed pause before attempting to fire up again.
This code is more frequent in spring and autumn when the heating is on but the house is already relatively warm, leading to shorter heating bursts.
DIY fix possible
Wait for 5 minutes for the display to clear naturallyCheck that your room thermostat is not set too close to the current room temperatureEnsure radiator valves are open to allow heat to move away from the boiler
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