BoilerFaultCodesYour boiler has shut down because it has detected it is getting too hot, which is often caused by trapped air or a blockage stopping the water from flowing.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Overheat – try bleeding your radiators
What causes this fault?
This fault occurs when water is unable to circulate through the boiler quickly enough to carry heat away from the burner, causing the internal temperature to rise to unsafe levels. The most common reason is a build-up of air or debris creating a blockage, or a mechanical failure of the pump that pushes the water around your system.
This error often appears when the heating is first turned on after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Check that all radiator valves and boiler isolation valves are fully open.Bled all your radiators using a radiator key to release any trapped air.Turn the boiler off and on again, or press the 'R' reset button for 5 seconds.
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 E125 — no call-out fees, no surprises.
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Baxi GA Range is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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