BoilerFaultCodesYour boiler has shut down because it detected that the water inside has become dangerously hot or overheated.
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, or
What causes this fault?
This fault occurs when the water leaving the boiler exceeds its safe temperature limit, causing the system to shut down for safety. The most common reasons are a pump failure that stops water from moving through the unit or a buildup of sludge and limescale that blocks the internal heat exchanger.
This fault is more common when the heating is first switched on in autumn, as circulation pumps can seize up after being inactive over the summer months.
DIY fix possible
Turn the boiler off and wait 30 minutes for it to cool down.Check that all radiator valves are fully open to allow water to circulate.Press the 'Reset' button on the front control panel.Ensure the system pressure gauge is between 1 and 1.5 bar.
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