BoilerFaultCodesYour boiler has switched itself off because it got too hot, and it needs to cool down before it can be restarted.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety cutout thermostat will extinguish the pilot and shut down the boiler in the event of overheating. Requires manual reset via button (E) after the boiler has cooled.
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, triggering a safety switch to shut everything down. The most common reasons are a failed pump that isn't moving water away from the boiler quickly enough or a blockage in the system pipework. It can also happen if the main control thermostat fails and allows the burner to stay on for too long.
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 internal pump to seize.
DIY fix possible
Wait at least 15-20 minutes for the boiler to cool down naturally.Locate the manual reset button (marked E) on the control panel.Press the button firmly and attempt to relight the pilot light following the instructions on the boiler's flap.
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