BoilerFaultCodesYour boiler has sensed it is getting too hot and has shut itself down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Overheat boiler lockout
What causes this fault?
This fault occurs when the water inside the heat exchanger reaches an unsafe temperature, triggering a safety shut-off to prevent damage. The most common reasons include a failing pump that isn't moving water away fast enough, a blockage in the system, or a faulty sensor misreading the temperature.
This issue is more frequent during autumn when heating is first turned back on after summer, as internal pump parts may have seized during the period of inactivity.
DIY fix possible
Check that your radiator valves are open and not turned to the off position.Ensure your system pressure is at the correct level (usually between 1.0 and 1.5 bar).Press and hold the 'R' or Reset button for a few seconds to see if the fault clears.
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A boiler cover plan would cover faults like 2 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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