BoilerFaultCodesYour boiler has shut down because it is getting too hot inside, usually because the water isn't moving around the system properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler temperature exceeded (circulation pump or air locked)
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature because it isn't being moved away into your radiators or hot water tap quickly enough. The most common reason is that the internal pump has failed or is stuck, but it can also be caused by a large air bubble trapped in the pipework blocking the flow.
This fault often appears at the start of autumn when the heating is turned back on after being off all summer, which can cause the pump to seize.
DIY fix possible
Check that all radiator valves are open and not turned off.Ensure there is enough water pressure in the system (typically 1.0 to 1.5 bar).Gently bleed your radiators to remove any trapped air that might be blocking water flow.
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A boiler cover plan would cover faults like E125 — no call-out fees, no surprises.
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