BoilerFaultCodesYour boiler has switched itself off because it has either become too hot or the water pressure in the system has dropped too low.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Low water pressure (sealed system), 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 exceeds a safe temperature or there isn't enough water circulating to carry heat away from the burner. The most common reasons are a build-up of air or debris blocking the pipes, a failing pump that can no longer move the water, or a simple drop in system pressure due to a leak.
This issue is frequently seen in autumn when the heating is turned on for the first time after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Check the pressure gauge on your system and top up to 1.5 bar if it is lowEnsure all radiator valves and boiler isolation valves are fully openPress the reset button on the control panel once the unit has cooled down
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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