BoilerFaultCodesTechnical description
Flue gas temperature exceeded
What causes this fault?
This fault occurs when the sensor detects that the gases produced by the burner have reached dangerously high temperatures. The most common reason is a buildup of scale or debris inside the heat exchanger which prevents heat from being transferred to the water effectively, or it could be due to a lack of proper water circulation. To prevent the internal components from melting or warping, the boiler shuts down as a critical safety precaution.
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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