BoilerFaultCodesTechnical description
Heat exchanger temperature exceeded (greater than 95 degrees)
What causes this fault?
This fault occurs when the water inside the boiler reaches a dangerously high temperature because it isn't moving away from the heat source quickly enough. The most common reason is a failed pump or a blockage in the system, such as a build-up of sludge or a stuck valve, which prevents the hot water from circulating to your radiators.
This issue often surfaces when the heating is first turned on after summer, as the internal pump or diverter valve 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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