BoilerFaultCodesTechnical description
Appliance overheat
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit, causing the system to shut down to prevent internal damage. The most common reasons are a pump failure that stops water from moving or a blockage in the heat exchanger that restricts flow. It can also be triggered by a build-up of air or sludge within the pipework that prevents heat from being carried away from the burner.
This issue often appears 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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