BoilerFaultCodesYour boiler has become too hot and has automatically shut itself down to prevent damage or safety issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The overheat thermostat will shut down the boiler in the event of overheating
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 include a pump failure that stops water from moving or a blockage within the pipework that traps heat inside the unit.
This issue is more frequent during the first cold spell of autumn, when pumps that have been idle all summer often seize up upon being restarted.
DIY fix possible
Check that your radiator valves are fully open to allow water flowEnsure there is enough water pressure in the system (typically 1 to 1.5 bar on the gauge)Wait for the boiler to cool down and press the reset button
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like Fault led (B) illuminated (Overheat) — no call-out fees, no surprises.
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Ideal Europa 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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