BoilerFaultCodesYour boiler has become too hot and has shut itself 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: Overheat fault
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, triggering a safety sensor to cut the power. The most common reasons are a pump failure that stops water from moving or a blockage in the heat exchanger that traps heat inside the unit.
This issue is more frequent 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 are open and not turned off.Ensure there is enough water pressure in the system (typically between 1 and 1.5 bar).Press the reset button on the control panel once the boiler has cooled down.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 05 — 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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