BoilerFaultCodesTechnical description
Safety temperature exceeded
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, causing the system to shut down to prevent damage. The most common reason is that water isn't moving through the unit quickly enough, often due to a pump failure, a build-up of sludge, or air trapped in the heat exchanger.
This issue often surfaces when the heating is first turned on after summer, as the internal pump can seize up after 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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