BoilerFaultCodesTechnical description
Flow sensor temperature exceeded
What causes this fault?
This fault occurs when the water leaving the boiler gets too hot too quickly, causing the system to shut down for safety. The most common reasons are a pump failure that stops water from moving or a blockage like sludge or trapped air preventing flow through the heat exchanger.
This issue is more common when the heating is first turned on after summer, as the internal pump can seize up after 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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