BoilerFaultCodesYour boiler has switched itself off because it has reached an unsafe temperature or a safety sensor has detected a fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: 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 gets too hot, causing a safety switch to trip and shut the system down to prevent damage. The most common reasons are a pump failure that stops water from moving or a buildup of sludge and scale that blocks the flow through the heat exchanger.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause the pump to seize.
DIY fix possible
Locate the overheat reset button under the boiler control panelPress the button firmly to reset the tripEnsure all radiator valves are open to allow water to circulate
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
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