BoilerFaultCodesYour boiler has detected that the exhaust gases are getting too hot, which can indicate a safety issue or missing internal parts.
Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now — this fault can be dangerous if ignored.
Technical description: Flue overheat: Flue temperature too high; Heat exchanger baffles have been removed and not refitted.
What causes this fault?
This fault occurs when the internal temperature of the exhaust gases exceeds safe limits, triggering a safety shutdown to prevent damage. The most common reason is that internal metal plates called baffles, which are designed to slow down and cool the heat, have been removed during a service and not put back, or the main heat exchanger is so dirty that it can no longer absorb heat correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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