BoilerFaultCodesYour boiler has shut down because the water inside it has become too hot, causing it to overheat for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Lockout temperature exceeded
What causes this fault?
This fault occurs when water cannot circulate through the boiler quickly enough to carry heat away, causing the internal temperature to reach a dangerous level. The most common reasons are a failed pump that isn't pushing water around, a blockage in the pipework, or air trapped within the heat exchanger. It acts as a safety 'trip' to prevent the appliance from being damaged by extreme heat.
This fault often appears when the heating is first turned on after summer, as the internal pump can seize up from months of inactivity.
DIY fix possible
Check that all radiator valves are fully open to allow water to flow.Ensure your system pressure is between 1.0 and 1.5 bar on the gauge.Press the 'reset' button on the boiler control panel once the unit has cooled down.
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A boiler cover plan would cover faults like E02 — 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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