BoilerFaultCodesYour boiler has reached an unsafe temperature and has shut down to prevent damage or overheating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Temperature of the boiler too high.
What causes this fault?
This fault occurs when the water inside the boiler gets too hot too quickly, usually because it isn't moving through the system fast enough to carry the heat away. The most common reasons are a failed pump that isn't pushing the water or a physical blockage, such as sludge or trapped air, stopping the flow through the heat exchanger.
This fault is more common when the heating is first turned on in autumn, as pumps can seize up after being idle during the summer months.
DIY fix possible
Check that all radiator valves are fully open to allow water to circulateEnsure there is enough pressure in the system by checking the pressure gauge (aim for 1.5 bar)Bleed any air out of your radiators using a radiator keyPress the Reset button once the boiler 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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