BoilerFaultCodesYour boiler has switched itself off because it has reached too high a temperature, likely due to trapped air or a blockage stopping water from circulating.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Overheated – try bleeding your radiators
What causes this fault?
This fault occurs when the water inside your boiler becomes too hot, causing a safety sensor to trip and shut the system down to prevent damage. The most common reason is that the water cannot move around the system properly, often due to an airlock in the pipework or a pump that has failed. It can also happen if your radiator valves are all closed or if there is a physical blockage restricting the flow.
This fault is frequently seen in autumn when heating systems are turned back on after a long summer break, as pump components can seize up from lack of use.
DIY fix possible
Turn off the boiler and allow it to cool down completely.Use a radiator key to bleed all radiators to remove any trapped air.Check the boiler pressure gauge and top it up to 1.5 bar if it has dropped.Turn the boiler back on and press the 'Reset' button.
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Could it be time for a new boiler?
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