BoilerFaultCodesTechnical description
Flow temperature exceeded
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature because it isn't moving away from the heat source quickly enough. The most common reasons are a failed pump that can no longer circulate the water or a blockage in the system pipes, often caused by a buildup of sludge or debris. In some cases, a faulty sensor may simply be misreading the temperature even if the water is flowing correctly.
This fault is more common in autumn and winter when the heating is first switched on after being idle, as pump components can seize up during the summer months.
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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