BoilerFaultCodesTechnical description
The temperature captured by the flow temperature sensor exceeded 105°c
What causes this fault?
This fault occurs when water inside the boiler isn't moving away from the heat source quickly enough, causing it to overheat rapidly. The most common reason is a failed circulation pump or a blockage in the pipework that prevents the water from flowing. In some cases, a build-up of debris or limescale inside the heat exchanger can also restrict movement and trap heat.
This issue often surfaces during the first cold spell of autumn when the heating is turned on after being dormant all summer, which can cause internal pump parts to seize.
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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