BoilerFaultCodesYour boiler has shut down because the internal water temperature has become too hot, likely due to a lack of water flow or a circulation problem.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow temperature too high
What causes this fault?
This fault occurs when the water inside the boiler heats up too quickly or reaches an unsafe temperature, forcing the system to shut down for safety. The most common reason is a failure in the circulation pump or a blockage in the pipes, which prevents the hot water from moving away from the burner. It can also be caused by a faulty sensor that is incorrectly reporting the water temperature to the control board.
This issue often appears when the heating is first turned on after summer, as circulation pumps can seize up if they haven't been used for several months.
DIY fix possible
Check if all radiator valves are open to ensure water can flow.Check the boiler pressure gauge and top up to 1.5 bar if it is too low.Restart the boiler using the reset button to see if the fault clears.
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