BoilerFaultCodesYour boiler has become too hot and has automatically shut itself down to prevent damage or safety issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Reset Button - Boiler overheat thermostat
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, triggering a safety switch to cut the power. The most common reasons include a failing pump that isn't moving water away quickly enough or a buildup of limescale and sludge that restricts flow through the heat exchanger.
This issue is more frequent in autumn when heating systems are first turned on after a long summer break, as stagnant debris can settle and block the pump.
DIY fix possible
Wait at least 30 minutes for the boiler to cool down completely.Locate the reset button (usually behind the small circular flap or on the main control panel).Press and hold the reset button for five seconds to see if the boiler restarts.Check that your radiator valves are open and your system pressure is between 1 and 1.5 bar.
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