BoilerFaultCodesTechnical description
Excessive temperature rise
What causes this fault?
This fault occurs when the water inside the boiler heats up at an unnaturally fast rate, causing the sensors to trigger a safety shutdown before the unit overheats. The most common reason is a lack of water flow, often caused by a failing internal pump or a blockage in the system that prevents heat from being moved away from the burner quickly enough.
This issue often appears when the heating is first turned on after summer, as the circulation 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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