BoilerFaultCodesYour boiler has shut down because it has detected it is getting too hot, which is usually caused by a lack of water or a circulation problem.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner in fault position. Temperature limiter has responded. Check the heating system water level, the pump and the lead for the temperature limiter.
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the heat exchanger has reached a dangerously high temperature, triggering a safety shutdown to prevent damage. The most common reasons are a failed internal pump that isn't moving water away from the burner quickly enough, or a significant air lock trap in the primary circuit. It can also be caused by a build-up of sludge blocking the flow of water through the narrow passages of the boiler.
This fault is more common in autumn when heating systems are first turned on after summer, as pumps can seize during long periods of inactivity.
DIY fix possible
Check the pressure gauge on your boiler and top up the water if it is below 1.5 barEnsure all your radiator valves are open and not switched offOnce the boiler has cooled down, press the 'Reset' button to see if the fault clears
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F2 — 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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