BoilerFaultCodesYour boiler has stopped running because it has either detected that it is getting too hot or the water pressure in the system has dropped too low.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low water pressure (sealed system), Overheat cut off device tripped or thermostat, overheat cut off device faulty
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe operating temperature or if there isn't enough water circulating to carry heat away. The most common reasons are a build-up of sludge blocking the heat exchanger, a failing pump, or a simple loss of pressure in the central heating pipes.
This issue often appears when the heating is first turned on in autumn, as pumps can seize after being inactive during the summer months.
DIY fix possible
Check the pressure gauge on your system and top it up to 1.5 bar using the filling loop if it is low.Ensure all radiator valves and boiler isolation valves are fully open to allow water flow.Wait for the unit to cool down and check if there is a manual reset button on the bottom or front of the casing.
Find a Gas Safe engineer
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