BoilerFaultCodesYour boiler has reached an unsafe temperature and has shut down to protect its internal components and your home's pipework.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Exceeded safety temperature
What causes this fault?
This fault occurs when the water inside the boiler gets too hot too quickly, causing the safety sensors to trigger an emergency shutdown. The most common reason is a lack of water flow, often caused by a failing pump or a blockage in the pipes that prevents heat from being carried away from the burner. It can also happen if there is a build-up of limescale or debris inside the heat exchanger, which traps heat and triggers the overheat sensor.
This fault is more common when the heating is first turned on after summer, as the circulation pump can seize up after long periods of inactivity.
DIY fix possible
Ensure all radiator valves are fully open to allow water to circulate.Check that your system water pressure is between 1.0 and 1.5 bar on the gauge.Restart the boiler using the 'Reset' button once the unit has cooled down.
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A boiler cover plan would cover faults like 110 — no call-out fees, no surprises.
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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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