BoilerFaultCodesYour boiler has shut down because it has detected internal temperatures that are dangerously high, triggering a safety cut-out to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Safety temperature limiter has pulled in
What causes this fault?
This fault occurs when the water inside the boiler gets too hot, causing a safety sensor to cut the power to prevent permanent damage. The most common reasons are a broken pump failing to move water away from the burner or a buildup of sludge and debris that blocks the internal pipework. In some cases, it may simply be caused by a faulty sensor that is incorrectly reporting a high temperature.
This fault is more common when the heating is first turned on after summer, as the internal pump can often seize up from long periods of inactivity.
DIY fix possible
Check that all radiator valves are fully open to allow water to circulate.Ensure your system pressure gauge is between 1 and 1.5 bar; top up if it is too low.Press the reset button once the boiler has had at least 20 minutes to cool down.
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A boiler cover plan would cover faults like E9 — no call-out fees, no surprises.
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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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