BoilerFaultCodesTechnical description
Temperature difference between flow and safety sensor exceeds limit
What causes this fault?
This fault occurs when the water inside the boiler heats up too quickly because it isn't circulating through your radiators or pipes as it should. The most common reasons are a failed internal pump that has stopped spinning, or a blockage caused by a buildup of sludge and debris within the main heat exchanger.
This fault often appears when heating is first turned on in autumn, as pumps can seize up after being inactive over 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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