BoilerFaultCodesYour boiler has shut down because it has overheated or detected a lack of water flow through the system.
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 state. Temperature limiter has responded. Cause: Check the heating system water level. Check the circulation pump. Vent the heating system. Check the temperature limiter and leads. Press E.
What causes this fault?
This fault occurs when the boiler's internal temperature reaches a dangerously high level, triggering a safety shutdown to prevent damage. The most common reasons are a pump failure that stops water from moving or a buildup of air and sludge that creates a blockage in the heat exchanger. Essentially, the burner is creating heat, but the system cannot move that heat away quickly enough.
This issue is frequently seen when the heating is first turned back on in autumn, as circulation pumps can seize up after sitting idle throughout the summer months.
DIY fix possible
Check the pressure gauge and top up water if it is below 1.5 barBleed your radiators to remove trapped airPress the 'Reset' or 'E' button to restart the boiler
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A boiler cover plan would cover faults like F2 — no call-out fees, no surprises.
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Viessmann Vitodens 333 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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