BoilerFaultCodesTechnical description
Safety sensor fault – temperature too high, sensor short circuit or open circuit
What causes this fault?
This fault occurs when the boiler's internal temperature exceeds safe limits, triggering an emergency shutdown to protect the components. The most common reasons are a lack of water flow caused by a stuck pump or a blockage, though it can also be triggered if the sensors themselves have failed or developed a wiring fault.
This issue often surfaces when the heating is first turned on after summer, as internal pumps can seize up during long periods of inactivity.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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