BoilerFaultCodesYour boiler has shut down because it has detected it is getting too hot, usually caused by a blockage or a pump failure.
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
What causes this fault?
This fault occurs when internal sensors detect that the water inside the boiler has exceeded a safe temperature limit, triggering an emergency shutdown to prevent damage. The most common reason is that the pump has stopped moving water around your radiators, or a buildup of debris has created a blockage that traps heat inside the unit.
This issue is frequently seen when the heating is first switched on after summer, as circulating pumps can often seize up during long periods of inactivity.
DIY fix possible
Check that your pump is running and hasn't seizedEnsure all radiator valves are open to allow water to flowWait for the boiler to cool down and press the reset button located underneath the unit
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