BoilerFaultCodesYour boiler has become too hot internally and has shut down as a safety precaution 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: Flashing lamp, alone or simultaneously with another lamp.
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature, causing the system to shut down to prevent internal damage. The most common reasons are a pump failure that stops water from moving or a blockage in the heat exchanger that prevents heat from escaping the boiler efficiently.
This issue often appears when the heating is first turned on after summer, as the internal pump can seize up from periods of inactivity.
DIY fix possible
Check that all radiator valves are fully openEnsure the system water pressure is between 1 and 1.5 bar on the pressure gaugeSwitch the boiler off and on again (Reset) to see if the fault clears after it cools down
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Excessive temperature on primary circuit — no call-out fees, no surprises.
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Ideal Mini HE 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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