BoilerFaultCodesYour boiler has become too hot and has automatically shut itself down to prevent damage and ensure safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler Overheat Thermostat: This thermostat will shut down the boiler in the event of overheating
What causes this fault?
This fault occurs when the water temperature inside the boiler exceeds a safe limit, causing the safety sensors to cut the power. The most common reasons are a pump failure that stops water from moving or a blockage in the system that prevents heat from being carried away from the boiler.
This issue is more frequent in autumn or winter when the heating is first turned on after a long summer break, as internal pumps are prone to seizing up during periods of inactivity.
DIY fix possible
Check that your radiator valves are openEnsure there is enough water pressure in the system (usually between 1 and 1.5 bar on the gauge)Once the boiler has cooled down, press the reset button on the front control panel
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
A boiler cover plan would cover faults like L-A — no call-out fees, no surprises.
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