BoilerFaultCodesTechnical description
Excessive temperature rise
What causes this fault?
This fault occurs because the water inside the boiler is getting too hot too quickly, often because something is blocking the flow or the pump has failed. The most common reasons include a buildup of internal debris like lime scale or sludge, or a mechanical failure that prevents the water from circulating around your radiators.
This fault is frequently seen in autumn when heating systems are switched back on after a long summer break, as pumps can seize up during 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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