BoilerFaultCodesTechnical description
Flue extraction duct safety device intervention
What causes this fault?
This fault occurs when the boiler's safety sensors detect that exhaust fumes are not being safely cleared through the flue pipe to the outside. The most common reasons are a blockage in the chimney or a mechanical failure in the fan that pushes the gases away. Because these fumes can be dangerous, the boiler shuts down immediately as a protective measure.
This fault is more common during periods of high winds, which can create back-pressure in the flue and trigger the safety sensor.
Engineer required
This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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