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: Temperature too high
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit, causing the system to shut down for safety. The most common reasons are a failed pump that isn't moving water around the radiators or a buildup of sludge and limescale that is restricting flow through the heat exchanger.
This fault is often seen when heating is first turned on after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Check that your boiler pressure is between 1 and 1.5 bar on the gauge.Ensure all radiator valves are fully open to allow water to flow.Check for any obvious obstructions in the external flue pipe.Reset the boiler by pressing the 'Reset' button once the temperature has cooled down.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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