BoilerFaultCodesTechnical description
Number of safety temperature cut offs
What causes this fault?
This fault occurs when the boiler's internal water temperature exceeds safe limits, forcing the system to shut down to prevent damage. The most common reason is a lack of water circulation, often caused by a failing pump or a blockage in the heat exchanger that prevents heat from leaving the unit. It can also be triggered by faulty sensors that are incorrectly reading the system temperature.
This issue often surfaces when the heating is first turned on after summer, as pump components 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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