BoilerFaultCodesYour boiler has shut down because it has detected that the water inside is getting too hot, known as overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: All Boilers
What causes this fault?
This fault occurs when the water inside the unit reaches an unsafe temperature, triggering a safety shutdown to prevent internal damage. It is usually caused by a blockage in the system, a pump failure that stops water from moving, or a buildup of limescale inside the heat exchanger. Essentially, the heat being produced by the burner is not being carried away fast enough by the circulating water.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause internal pumps to seize.
DIY fix possible
Wait 20 to 30 minutes for the system to cool down completely.Ensure all radiator valves are fully open to allow water to flow.Press the 'Reset' button on the front control panel to restart the boiler.
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